[FEATURE] Add config and use composer autoloader.

We use composer already to install SabreDAV. Include config
composer.(json|lock) to install and manage more dependencies
in future.
Also provide PSR-4 autoloading for our namespaced classes, e.g.
"Zotlabs\". To regenerate autoloader maps use:
$ composer install --optimize-autoloader --no-dev

We could also remove the whole vendor/ folder from our repository, but
that would need changes in deployment and how to install hubs and needs
more discussion first.

28 files changed, 513 insertions, 100 deletions

diff --git a/vendor/sabre/dav/composer.json b/vendor/sabre/dav/composer.json
new file mode 100644
index 000000000..f85d9655e
--- /dev/null
+++ b/vendor/sabre/dav/composer.json
@@ -0,0 +1,68 @@
+{
+    "name": "sabre/dav",
+    "type": "library",
+    "description": "WebDAV Framework for PHP",
+    "keywords": ["Framework", "WebDAV", "CalDAV", "CardDAV", "iCalendar"],
+    "homepage": "http://sabre.io/",
+    "license" : "BSD-3-Clause",
+    "authors": [
+        {
+            "name": "Evert Pot",
+            "email": "me@evertpot.com",
+            "homepage" : "http://evertpot.com/",
+            "role" : "Developer"
+        }
+    ],
+    "require": {
+        "php": ">=5.5.0",
+        "sabre/vobject": "^4.1.0",
+        "sabre/event" : ">=2.0.0, <4.0.0",
+        "sabre/xml"  : "^1.4.0",
+        "sabre/http" : "^4.2.1",
+        "sabre/uri" : "^1.0.1",
+        "ext-dom": "*",
+        "ext-pcre": "*",
+        "ext-spl": "*",
+        "ext-simplexml": "*",
+        "ext-mbstring" : "*",
+        "ext-ctype" : "*",
+        "ext-date" : "*",
+        "ext-iconv" : "*",
+        "lib-libxml" : ">=2.7.0",
+        "psr/log": "^1.0"
+    },
+    "require-dev" : {
+        "phpunit/phpunit" : "> 4.8, <=6.0.0",
+        "evert/phpdoc-md" : "~0.1.0",
+        "sabre/cs"        : "~0.0.5",
+        "monolog/monolog": "^1.18"
+    },
+    "suggest" : {
+        "ext-curl" : "*",
+        "ext-pdo" : "*"
+    },
+    "autoload": {
+        "psr-4" : {
+            "Sabre\\DAV\\"     : "lib/DAV/",
+            "Sabre\\DAVACL\\"  : "lib/DAVACL/",
+            "Sabre\\CalDAV\\"  : "lib/CalDAV/",
+            "Sabre\\CardDAV\\" : "lib/CardDAV/"
+        }
+    },
+    "support" : {
+        "forum" : "https://groups.google.com/group/sabredav-discuss",
+        "source" : "https://github.com/fruux/sabre-dav"
+    },
+    "bin" : [
+        "bin/sabredav",
+        "bin/naturalselection"
+    ],
+    "config" : {
+        "bin-dir" : "./bin"
+    },
+    "extra" : {
+        "branch-alias": {
+            "dev-master": "3.1.0-dev"
+        }
+    }
+}
diff --git a/vendor/sabre/dav/lib/DAV/Browser/Plugin.php b/vendor/sabre/dav/lib/DAV/Browser/Plugin.php
index 4959193ea..49359a045 100644
--- a/vendor/sabre/dav/lib/DAV/Browser/Plugin.php
+++ b/vendor/sabre/dav/lib/DAV/Browser/Plugin.php
@@ -163,7 +163,7 @@ class Plugin extends DAV\ServerPlugin {
      * @return bool
      */
     function httpPOST(RequestInterface $request, ResponseInterface $response) {
-			
+
         $contentType = $request->getHeader('Content-Type');
         list($contentType) = explode(';', $contentType);
         if ($contentType !== 'application/x-www-form-urlencoded' &&
@@ -179,7 +179,7 @@ class Plugin extends DAV\ServerPlugin {
 
         if ($this->server->emit('onBrowserPostAction', [$uri, $postVars['sabreAction'], $postVars])) {
 
-					switch ($postVars['sabreAction']) {
+            switch ($postVars['sabreAction']) {
 
                 case 'mkcol' :
                     if (isset($postVars['name']) && trim($postVars['name'])) {
@@ -221,7 +221,7 @@ class Plugin extends DAV\ServerPlugin {
 
                     if ($_FILES) $file = current($_FILES);
                     else break;
-										
+
                     list(, $newName) = URLUtil::splitPath(trim($file['name']));
                     if (isset($postVars['name']) && trim($postVars['name']))
                         $newName = trim($postVars['name']);
diff --git a/vendor/sabre/event/composer.json b/vendor/sabre/event/composer.json
new file mode 100644
index 000000000..9a11b01aa
--- /dev/null
+++ b/vendor/sabre/event/composer.json
@@ -0,0 +1,47 @@
+{
+    "name": "sabre/event",
+    "description": "sabre/event is a library for lightweight event-based programming",
+    "keywords": [
+        "Events",
+        "EventEmitter",
+        "Promise",
+        "Hooks",
+        "Plugin",
+        "Signal",
+        "Async"
+    ],
+    "homepage": "http://sabre.io/event/",
+    "license": "BSD-3-Clause",
+    "require": {
+        "php": ">=5.5"
+    },
+    "authors": [
+        {
+            "name": "Evert Pot",
+            "email": "me@evertpot.com",
+            "homepage": "http://evertpot.com/",
+            "role": "Developer"
+        }
+    ],
+    "support": {
+        "forum": "https://groups.google.com/group/sabredav-discuss",
+        "source": "https://github.com/fruux/sabre-event"
+    },
+    "autoload": {
+        "psr-4": {
+            "Sabre\\Event\\": "lib/"
+        },
+        "files" : [
+            "lib/coroutine.php",
+            "lib/Loop/functions.php",
+            "lib/Promise/functions.php"
+        ]
+    },
+    "require-dev": {
+        "sabre/cs": "~0.0.4",
+        "phpunit/phpunit" : "*"
+    },
+    "config" : {
+        "bin-dir" : "bin/"
+    }
+}
diff --git a/vendor/sabre/http/composer.json b/vendor/sabre/http/composer.json
new file mode 100644
index 000000000..b061194cf
--- /dev/null
+++ b/vendor/sabre/http/composer.json
@@ -0,0 +1,43 @@
+{
+    "name": "sabre/http",
+    "description" : "The sabre/http library provides utilities for dealing with http requests and responses. ",
+    "keywords" : [ "HTTP" ],
+    "homepage" : "https://github.com/fruux/sabre-http",
+    "license" : "BSD-3-Clause",
+    "require" : {
+        "php"          : ">=5.4",
+        "ext-mbstring" : "*",
+        "sabre/event"  : ">=1.0.0,<4.0.0",
+        "sabre/uri"    : "~1.0"
+    },
+    "require-dev" : {
+        "phpunit/phpunit" : "~4.3",
+        "sabre/cs" : "~0.0.1"
+    },
+    "suggest" : {
+        "ext-curl" : " to make http requests with the Client class"
+    },
+    "authors" : [
+        {
+            "name" : "Evert Pot",
+            "email" : "me@evertpot.com",
+            "homepage" : "http://evertpot.com/",
+            "role" : "Developer"
+        }
+    ],
+    "support" : {
+        "forum" : "https://groups.google.com/group/sabredav-discuss",
+        "source" : "https://github.com/fruux/sabre-http"
+    },
+    "autoload" : {
+        "files" : [
+            "lib/functions.php"
+        ],
+        "psr-4" : {
+            "Sabre\\HTTP\\" : "lib/"
+        }
+    },
+    "config" : {
+        "bin-dir" : "bin/"
+    }
+}
diff --git a/vendor/sabre/uri/composer.json b/vendor/sabre/uri/composer.json
new file mode 100644
index 000000000..7b48acb71
--- /dev/null
+++ b/vendor/sabre/uri/composer.json
@@ -0,0 +1,41 @@
+{
+    "name": "sabre/uri",
+    "description": "Functions for making sense out of URIs.",
+    "keywords": [
+        "URI",
+        "URL",
+        "rfc3986"
+    ],
+    "homepage": "http://sabre.io/uri/",
+    "license": "BSD-3-Clause",
+    "require": {
+        "php": ">=5.4.7"
+    },
+    "authors": [
+        {
+            "name": "Evert Pot",
+            "email": "me@evertpot.com",
+            "homepage": "http://evertpot.com/",
+            "role": "Developer"
+        }
+    ],
+    "support": {
+        "forum": "https://groups.google.com/group/sabredav-discuss",
+        "source": "https://github.com/fruux/sabre-uri"
+    },
+    "autoload": {
+        "files" : [
+            "lib/functions.php"
+        ],
+        "psr-4" : {
+            "Sabre\\Uri\\" : "lib/"
+        }
+    },
+    "require-dev": {
+        "sabre/cs": "~0.0.1",
+        "phpunit/phpunit" : "*"
+    },
+    "config" : {
+        "bin-dir" : "bin/"
+    }
+}
diff --git a/vendor/sabre/vobject/.travis.yml b/vendor/sabre/vobject/.travis.yml
index 06bbdf8a0..b7266a878 100644
--- a/vendor/sabre/vobject/.travis.yml
+++ b/vendor/sabre/vobject/.travis.yml
@@ -3,14 +3,9 @@ php:
   - 5.5
   - 5.6
   - 7
-  - hhvm
 
 sudo: false
 
-matrix:
-  allow_failures:
-    - php: hhvm
-
 script:
   - phpunit --configuration tests/phpunit.xml
   - ./bin/sabre-cs-fixer fix . --dry-run --diff
diff --git a/vendor/sabre/vobject/CHANGELOG.md b/vendor/sabre/vobject/CHANGELOG.md
index 0bd7d53bd..4c72680f8 100644
--- a/vendor/sabre/vobject/CHANGELOG.md
+++ b/vendor/sabre/vobject/CHANGELOG.md
@@ -1,6 +1,19 @@
 ChangeLog
 =========
 
+4.1.1 (2016-07-15)
+------------------
+
+* #327: Throwing `InvalidDataException` in more cases where invalid iCalendar
+  dates and times were provided. (@rsto)
+* #331: Fix dealing with multiple overridden instances falling on the same
+  date/time (@afedyk-sugarcrm).
+* #333: Fix endless loop on invalid `BYMONTH` values in recurrence.
+  (@PHPGangsta)
+* #339: Fixed a few `validate()` results when repair is off. (@PHPGangsta)
+* #338: Stripping invalid `BYMONTH=` rules during `validate()` (@PHPGangsta)
+* #336: Fix incorrect `BYSECOND=` validation. (@PHPGangsta)
+
 
 4.1.0 (2016-04-06)
 ------------------
@@ -130,6 +143,20 @@ ChangeLog
   and `IntegerValue` to allow PHP 7 compatibility.
 
 
+3.5.3 (????-??-??)
+------------------
+
+* #331: Fix dealing with multiple overridden instances falling on the same
+  date/time (@afedyk-sugarcrm).
+
+
+3.5.2 (2016-04-24)
+-----------------
+
+* #312: Backported a fix related to iTip processing of events with timezones,
+  without a master event.
+
+
 3.5.1 (2016-04-06)
 ------------------
 
diff --git a/vendor/sabre/vobject/bin/bench.php b/vendor/sabre/vobject/bin/bench.php
index 807b40777..807b40777 100644..100755
--- a/vendor/sabre/vobject/bin/bench.php
+++ b/vendor/sabre/vobject/bin/bench.php
diff --git a/vendor/sabre/vobject/bin/fetch_windows_zones.php b/vendor/sabre/vobject/bin/fetch_windows_zones.php
index 1b1fdc37c..1b1fdc37c 100644..100755
--- a/vendor/sabre/vobject/bin/fetch_windows_zones.php
+++ b/vendor/sabre/vobject/bin/fetch_windows_zones.php
diff --git a/vendor/sabre/vobject/bin/generateicalendardata.php b/vendor/sabre/vobject/bin/generateicalendardata.php
index dfcf18780..a2df3c63a 100644..100755
--- a/vendor/sabre/vobject/bin/generateicalendardata.php
+++ b/vendor/sabre/vobject/bin/generateicalendardata.php
@@ -29,7 +29,7 @@ include __DIR__ . '/../vendor/autoload.php';
 
 fwrite(STDERR, "Generating " . $events . " events\n");
 
-$currentDate = new DateTime('-' . round($events / 2) .  ' days');
+$currentDate = new DateTime('-' . round($events / 2) . ' days');
 
 $calendar = new VObject\Component\VCalendar();
 
diff --git a/vendor/sabre/vobject/bin/mergeduplicates.php b/vendor/sabre/vobject/bin/mergeduplicates.php
index 1662e7bf3..076524d36 100644..100755
--- a/vendor/sabre/vobject/bin/mergeduplicates.php
+++ b/vendor/sabre/vobject/bin/mergeduplicates.php
@@ -157,7 +157,7 @@ while ($vcard = $splitter->getNext()) {
 
                 // echo $newProp->serialize() . " does not appear in earlier vcard!\n";
                 $stats['Error']++;
-                if ($debug) fwrite($debug, "Missing '" . $newProp->name .  "' property in duplicate. Earlier vcard:\n" . $collectedNames[$fn]->serialize() . "\n\nLater:\n" . $vcard->serialize() . "\n\n");
+                if ($debug) fwrite($debug, "Missing '" . $newProp->name . "' property in duplicate. Earlier vcard:\n" . $collectedNames[$fn]->serialize() . "\n\nLater:\n" . $vcard->serialize() . "\n\n");
                 
                 $vcard->destroy();
                 continue 2;
diff --git a/vendor/sabre/vobject/composer.json b/vendor/sabre/vobject/composer.json
new file mode 100644
index 000000000..bd6348a82
--- /dev/null
+++ b/vendor/sabre/vobject/composer.json
@@ -0,0 +1,88 @@
+{
+    "name": "sabre/vobject",
+    "description" : "The VObject library for PHP allows you to easily parse and manipulate iCalendar and vCard objects",
+    "keywords" : [
+        "iCalendar",
+        "iCal",
+        "vCalendar",
+        "vCard",
+        "jCard",
+        "jCal",
+        "ics",
+        "vcf",
+        "xCard",
+        "xCal",
+        "freebusy",
+        "recurrence",
+        "availability",
+        "rfc2425",
+        "rfc2426",
+        "rfc2739",
+        "rfc4770",
+        "rfc5545",
+        "rfc5546",
+        "rfc6321",
+        "rfc6350",
+        "rfc6351",
+        "rfc6474",
+        "rfc6638",
+        "rfc6715",
+        "rfc6868"
+    ],
+    "homepage" : "http://sabre.io/vobject/",
+    "license" : "BSD-3-Clause",
+    "require" : {
+        "php"          : ">=5.5",
+        "ext-mbstring" : "*",
+        "sabre/xml"    : "~1.1"
+    },
+    "require-dev" : {
+        "phpunit/phpunit" : "*",
+        "sabre/cs"        : "~0.0.3"
+
+    },
+    "suggest" : {
+        "hoa/bench"       : "If you would like to run the benchmark scripts"
+    },
+    "authors" : [
+        {
+            "name" : "Evert Pot",
+            "email" : "me@evertpot.com",
+            "homepage" : "http://evertpot.com/",
+            "role" : "Developer"
+        },
+        {
+            "name" : "Dominik Tobschall",
+            "email" : "dominik@fruux.com",
+            "homepage" : "http://tobschall.de/",
+            "role" : "Developer"
+        },
+        {
+            "name" : "Ivan Enderlin",
+            "email" : "ivan.enderlin@hoa-project.net",
+            "homepage" : "http://mnt.io/",
+            "role" : "Developer"
+        }
+    ],
+    "support" : {
+        "forum" : "https://groups.google.com/group/sabredav-discuss",
+        "source" : "https://github.com/fruux/sabre-vobject"
+    },
+    "autoload" : {
+        "psr-4" : {
+            "Sabre\\VObject\\" : "lib/"
+        }
+    },
+    "bin" : [
+        "bin/vobject",
+        "bin/generate_vcards"
+    ],
+    "extra" : {
+        "branch-alias" : {
+            "dev-master" : "4.0.x-dev"
+        }
+    },
+    "config" : {
+        "bin-dir" : "bin"
+    }
+}
diff --git a/vendor/sabre/vobject/lib/Component/VTimeZone.php b/vendor/sabre/vobject/lib/Component/VTimeZone.php
index d5d886947..f6eb6cba1 100644
--- a/vendor/sabre/vobject/lib/Component/VTimeZone.php
+++ b/vendor/sabre/vobject/lib/Component/VTimeZone.php
@@ -53,8 +53,7 @@ class VTimeZone extends VObject\Component {
             'LAST-MODIFIED' => '?',
             'TZURL'         => '?',
 
-            // At least 1 STANDARD or DAYLIGHT must appear, or more. But both
-            // cannot appear in the same VTIMEZONE.
+            // At least 1 STANDARD or DAYLIGHT must appear.
             //
             // The validator is not specific yet to pick this up, so these
             // rules are too loose.
diff --git a/vendor/sabre/vobject/lib/DateTimeParser.php b/vendor/sabre/vobject/lib/DateTimeParser.php
index fc568abb0..443bbb660 100644
--- a/vendor/sabre/vobject/lib/DateTimeParser.php
+++ b/vendor/sabre/vobject/lib/DateTimeParser.php
@@ -43,7 +43,12 @@ class DateTimeParser {
         if ($matches[7] === 'Z' || is_null($tz)) {
             $tz = new DateTimeZone('UTC');
         }
-        $date = new DateTimeImmutable($matches[1] . '-' . $matches[2] . '-' . $matches[3] . ' ' . $matches[4] . ':' . $matches[5] . ':' . $matches[6], $tz);
+
+        try {
+            $date = new DateTimeImmutable($matches[1] . '-' . $matches[2] . '-' . $matches[3] . ' ' . $matches[4] . ':' . $matches[5] . ':' . $matches[6], $tz);
+        } catch (\Exception $e) {
+            throw new InvalidDataException('The supplied iCalendar datetime value is incorrect: ' . $dt);
+        }
 
         return $date;
 
@@ -70,7 +75,11 @@ class DateTimeParser {
             $tz = new DateTimeZone('UTC');
         }
 
-        $date = new DateTimeImmutable($matches[1] . '-' . $matches[2] . '-' . $matches[3], $tz);
+        try {
+            $date = new DateTimeImmutable($matches[1] . '-' . $matches[2] . '-' . $matches[3], $tz);
+        } catch (\Exception $e) {
+            throw new InvalidDataException('The supplied iCalendar date value is incorrect: ' . $date);
+        }
 
         return $date;
 
diff --git a/vendor/sabre/vobject/lib/Property.php b/vendor/sabre/vobject/lib/Property.php
index 112775131..1aaa3ed58 100644
--- a/vendor/sabre/vobject/lib/Property.php
+++ b/vendor/sabre/vobject/lib/Property.php
@@ -579,7 +579,7 @@ abstract class Property extends Node {
         // Checking if the propertyname does not contain any invalid bytes.
         if (!preg_match('/^([A-Z0-9-]+)$/', $this->name)) {
             $warnings[] = [
-                'level'   => 1,
+                'level'   => $options & self::REPAIR ? 1 : 3,
                 'message' => 'The propertyname: ' . $this->name . ' contains invalid characters. Only A-Z, 0-9 and - are allowed',
                 'node'    => $this,
             ];
@@ -599,7 +599,7 @@ abstract class Property extends Node {
 
             if ($this->root->getDocumentType() === Document::VCARD40) {
                 $warnings[] = [
-                    'level'   => 1,
+                    'level'   => 3,
                     'message' => 'ENCODING parameter is not valid in vCard 4.',
                     'node'    => $this
                 ];
@@ -623,7 +623,7 @@ abstract class Property extends Node {
                 }
                 if ($allowedEncoding && !in_array(strtoupper($encoding), $allowedEncoding)) {
                     $warnings[] = [
-                        'level'   => 1,
+                        'level'   => 3,
                         'message' => 'ENCODING=' . strtoupper($encoding) . ' is not valid for this document type.',
                         'node'    => $this
                     ];
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/Recur.php b/vendor/sabre/vobject/lib/Property/ICalendar/Recur.php
index a3c36dc64..8392a5cc1 100644
--- a/vendor/sabre/vobject/lib/Property/ICalendar/Recur.php
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/Recur.php
@@ -260,21 +260,39 @@ class Recur extends Property {
 
         foreach ($values as $key => $value) {
 
-            if (empty($value)) {
+            if ($value === '') {
                 $warnings[] = [
-                    'level'   => $repair ? 3 : 1,
+                    'level'   => $repair ? 1 : 3,
                     'message' => 'Invalid value for ' . $key . ' in ' . $this->name,
                     'node'    => $this
                 ];
                 if ($repair) {
                     unset($values[$key]);
                 }
+            } elseif ($key == 'BYMONTH') {
+                $byMonth = (array)$value;
+                foreach ($byMonth as $i => $v) {
+                    if (!is_numeric($v) || (int)$v < 1 || (int)$v > 12) {
+                        $warnings[] = [
+                            'level'   => $repair ? 1 : 3,
+                            'message' => 'BYMONTH in RRULE must have value(s) between 1 and 12!',
+                            'node'    => $this
+                        ];
+                        if ($repair) {
+                            if (is_array($value)) {
+                                unset($values[$key][$i]);
+                            } else {
+                                unset($values[$key]);
+                            }
+                        }
+                    }
+                }
             }
 
         }
         if (!isset($values['FREQ'])) {
             $warnings[] = [
-                'level'   => $repair ? 3 : 1,
+                'level'   => $repair ? 1 : 3,
                 'message' => 'FREQ is required in ' . $this->name,
                 'node'    => $this
             ];
diff --git a/vendor/sabre/vobject/lib/Property/Text.php b/vendor/sabre/vobject/lib/Property/Text.php
index 2e16ac534..abc17563f 100644
--- a/vendor/sabre/vobject/lib/Property/Text.php
+++ b/vendor/sabre/vobject/lib/Property/Text.php
@@ -397,7 +397,7 @@ class Text extends Property {
             if (count($parts) < $minimum) {
                 $warnings[] = [
                     'level'   => $options & self::REPAIR ? 1 : 3,
-                    'message' => 'The ' . $this->name  . ' property must have at least ' . $minimum . ' values. It only has ' . count($parts),
+                    'message' => 'The ' . $this->name . ' property must have at least ' . $minimum . ' values. It only has ' . count($parts),
                     'node'    => $this,
                 ];
                 if ($options & self::REPAIR) {
diff --git a/vendor/sabre/vobject/lib/Recur/EventIterator.php b/vendor/sabre/vobject/lib/Recur/EventIterator.php
index 86c996aec..f91c336bc 100644
--- a/vendor/sabre/vobject/lib/Recur/EventIterator.php
+++ b/vendor/sabre/vobject/lib/Recur/EventIterator.php
@@ -325,7 +325,7 @@ class EventIterator implements \Iterator {
         $index = [];
         foreach ($this->overriddenEvents as $key => $event) {
             $stamp = $event->DTSTART->getDateTime($this->timeZone)->getTimeStamp();
-            $index[$stamp] = $key;
+            $index[$stamp][] = $key;
         }
         krsort($index);
         $this->counter = 0;
@@ -372,8 +372,9 @@ class EventIterator implements \Iterator {
         // overridden event may cut ahead.
         if ($this->overriddenEventsIndex) {
 
-            $offset = end($this->overriddenEventsIndex);
+            $offsets = end($this->overriddenEventsIndex);
             $timestamp = key($this->overriddenEventsIndex);
+            $offset = end($offsets);
             if (!$nextDate || $timestamp < $nextDate->getTimeStamp()) {
                 // Overridden event comes first.
                 $this->currentOverriddenEvent = $this->overriddenEvents[$offset];
@@ -383,7 +384,10 @@ class EventIterator implements \Iterator {
                 $this->currentDate = $this->currentOverriddenEvent->DTSTART->getDateTime($this->timeZone);
 
                 // Ensuring that this item will only be used once.
-                array_pop($this->overriddenEventsIndex);
+                array_pop($this->overriddenEventsIndex[$timestamp]);
+                if (!$this->overriddenEventsIndex[$timestamp]) {
+                    array_pop($this->overriddenEventsIndex);
+                }
 
                 // Exit point!
                 return;
@@ -451,7 +455,7 @@ class EventIterator implements \Iterator {
     /**
      * Overridden event index.
      *
-     * Key is timestamp, value is the index of the item in the $overriddenEvent
+     * Key is timestamp, value is the list of indexes of the item in the $overriddenEvent
      * property.
      *
      * @var array
diff --git a/vendor/sabre/vobject/lib/Recur/RRuleIterator.php b/vendor/sabre/vobject/lib/Recur/RRuleIterator.php
index 402e2de83..4c89f3ce4 100644
--- a/vendor/sabre/vobject/lib/Recur/RRuleIterator.php
+++ b/vendor/sabre/vobject/lib/Recur/RRuleIterator.php
@@ -718,6 +718,11 @@ class RRuleIterator implements Iterator {
 
                 case 'BYMONTH' :
                     $this->byMonth = (array)$value;
+                    foreach ($this->byMonth as $byMonth) {
+                        if (!is_numeric($byMonth) || (int)$byMonth < 1 || (int)$byMonth > 12) {
+                            throw new InvalidDataException('BYMONTH in RRULE must have value(s) betweeen 1 and 12!');
+                        }
+                    }
                     break;
 
                 case 'BYSETPOS' :
diff --git a/vendor/sabre/vobject/lib/TimeZoneUtil.php b/vendor/sabre/vobject/lib/TimeZoneUtil.php
index 4873daf92..2a95ae898 100644
--- a/vendor/sabre/vobject/lib/TimeZoneUtil.php
+++ b/vendor/sabre/vobject/lib/TimeZoneUtil.php
@@ -240,10 +240,10 @@ class TimeZoneUtil {
         if (!is_null(self::$map)) return;
 
         self::$map = array_merge(
-            include __DIR__ .  '/timezonedata/windowszones.php',
-            include __DIR__ .  '/timezonedata/lotuszones.php',
-            include __DIR__ .  '/timezonedata/exchangezones.php',
-            include __DIR__ .  '/timezonedata/php-workaround.php'
+            include __DIR__ . '/timezonedata/windowszones.php',
+            include __DIR__ . '/timezonedata/lotuszones.php',
+            include __DIR__ . '/timezonedata/exchangezones.php',
+            include __DIR__ . '/timezonedata/php-workaround.php'
         );
 
     }
@@ -260,7 +260,7 @@ class TimeZoneUtil {
      * @return array
      */
     static function getIdentifiersBC() {
-        return include __DIR__ .  '/timezonedata/php-bc.php';
+        return include __DIR__ . '/timezonedata/php-bc.php';
     }
 
 }
diff --git a/vendor/sabre/vobject/lib/Version.php b/vendor/sabre/vobject/lib/Version.php
index 0b0e16c03..ca9f21960 100644
--- a/vendor/sabre/vobject/lib/Version.php
+++ b/vendor/sabre/vobject/lib/Version.php
@@ -14,6 +14,6 @@ class Version {
     /**
      * Full version number.
      */
-    const VERSION = '4.1.0';
+    const VERSION = '4.1.1';
 
 }
diff --git a/vendor/sabre/xml/.travis.yml b/vendor/sabre/xml/.travis.yml
index 9bba4d451..96396564e 100644
--- a/vendor/sabre/xml/.travis.yml
+++ b/vendor/sabre/xml/.travis.yml
@@ -1,11 +1,9 @@
 language: php
 php:
-  - 5.4
   - 5.5
   - 5.6
-  - 7
-  - nightly
-  - hhvm
+  - 7.0
+  - 7.1
 
 matrix:
   fast_finish: true
@@ -16,10 +14,13 @@ cache:
   directories:
     - $HOME/.composer/cache
 
+before_install:
+  - phpenv config-rm xdebug.ini; true
+
+install:
+  - composer install
+
 script:
   - ./bin/phpunit --configuration tests/phpunit.xml.dist
   - ./bin/sabre-cs-fixer fix . --dry-run --diff
 
-before_script:
-  - phpenv config-rm xdebug.ini; true
-  - composer install
diff --git a/vendor/sabre/xml/CHANGELOG.md b/vendor/sabre/xml/CHANGELOG.md
index a8085401b..39a39bffe 100644
--- a/vendor/sabre/xml/CHANGELOG.md
+++ b/vendor/sabre/xml/CHANGELOG.md
@@ -1,7 +1,16 @@
 ChangeLog
 =========
 
-1.4.2 (????-??-??)
+1.5.0 (2016-10-09)
+------------------
+
+* Now requires PHP 5.5.
+* Using `finally` to always roll back the context stack when serializing.
+* #94: Fixed an infinite loop condition when reading some invalid XML
+  documents.
+
+
+1.4.2 (2016-05-19)
 ------------------
 
 * The `contextStack` in the Reader object is now correctly rolled back in
diff --git a/vendor/sabre/xml/composer.json b/vendor/sabre/xml/composer.json
new file mode 100644
index 000000000..386f8213f
--- /dev/null
+++ b/vendor/sabre/xml/composer.json
@@ -0,0 +1,53 @@
+{
+    "name": "sabre/xml",
+    "description" : "sabre/xml is an XML library that you may not hate.",
+    "keywords" : [ "XML", "XMLReader", "XMLWriter", "DOM" ],
+    "homepage" : "https://sabre.io/xml/",
+    "license" : "BSD-3-Clause",
+    "require" : {
+        "php" : ">=5.5.5",
+        "ext-xmlwriter" : "*",
+        "ext-xmlreader" : "*",
+        "ext-dom" : "*",
+        "lib-libxml" : ">=2.6.20",
+        "sabre/uri" : ">=1.0,<3.0.0"
+    },
+    "authors" : [
+        {
+            "name" : "Evert Pot",
+            "email" : "me@evertpot.com",
+            "homepage" : "http://evertpot.com/",
+            "role" : "Developer"
+        },
+        {
+            "name": "Markus Staab",
+            "email": "markus.staab@redaxo.de",
+            "role" : "Developer"
+        }
+    ],
+    "support" : {
+        "forum" : "https://groups.google.com/group/sabredav-discuss",
+        "source" : "https://github.com/fruux/sabre-xml"
+    },
+    "autoload" : {
+        "psr-4" : {
+            "Sabre\\Xml\\" : "lib/"
+        },
+        "files": [
+            "lib/Deserializer/functions.php",
+            "lib/Serializer/functions.php"
+        ]
+    },
+    "autoload-dev" : {
+        "psr-4" : {
+            "Sabre\\Xml\\" : "tests/Sabre/Xml/"
+        }
+    },
+    "require-dev": {
+        "sabre/cs": "~1.0.0",
+        "phpunit/phpunit" : "*"
+    },
+    "config" : {
+        "bin-dir" : "bin/"
+    }
+}
diff --git a/vendor/sabre/xml/lib/Element/XmlFragment.php b/vendor/sabre/xml/lib/Element/XmlFragment.php
index 0abfac132..642241ca4 100644
--- a/vendor/sabre/xml/lib/Element/XmlFragment.php
+++ b/vendor/sabre/xml/lib/Element/XmlFragment.php
@@ -2,9 +2,9 @@
 
 namespace Sabre\Xml\Element;
 
+use Sabre\Xml\Element;
 use Sabre\Xml\Reader;
 use Sabre\Xml\Writer;
-use Sabre\Xml\Element;
 
 /**
  * The XmlFragment element allows you to extract a portion of your xml tree,
diff --git a/vendor/sabre/xml/lib/Reader.php b/vendor/sabre/xml/lib/Reader.php
index f35dc8537..92e5dba96 100644
--- a/vendor/sabre/xml/lib/Reader.php
+++ b/vendor/sabre/xml/lib/Reader.php
@@ -59,22 +59,26 @@ class Reader extends XMLReader {
         $previousEntityState = libxml_disable_entity_loader(true);
         $previousSetting = libxml_use_internal_errors(true);
 
-        // Really sorry about the silence operator, seems like I have no
-        // choice. See:
-        //
-        // https://bugs.php.net/bug.php?id=64230
-        while ($this->nodeType !== self::ELEMENT && @$this->read()) {
-            // noop
-        }
-        $result = $this->parseCurrentElement();
+        try {
+
+            // Really sorry about the silence operator, seems like I have no
+            // choice. See:
+            //
+            // https://bugs.php.net/bug.php?id=64230
+            while ($this->nodeType !== self::ELEMENT && @$this->read()) {
+                // noop
+            }
+            $result = $this->parseCurrentElement();
 
-        $errors = libxml_get_errors();
-        libxml_clear_errors();
-        libxml_use_internal_errors($previousSetting);
-        libxml_disable_entity_loader($previousEntityState);
+            $errors = libxml_get_errors();
+            libxml_clear_errors();
+            if ($errors) {
+                throw new LibXMLException($errors);
+            }
 
-        if ($errors) {
-            throw new LibXMLException($errors);
+        } finally {
+            libxml_use_internal_errors($previousSetting);
+            libxml_disable_entity_loader($previousEntityState);
         }
 
         return $result;
@@ -138,60 +142,62 @@ class Reader extends XMLReader {
             $this->elementMap = $elementMap;
         }
 
-        // Really sorry about the silence operator, seems like I have no
-        // choice. See:
-        //
-        // https://bugs.php.net/bug.php?id=64230
-        if (!@$this->read()) {
-            if (!is_null($elementMap)) {
-                $this->popContext();
-            }
-            return false;
-        }
-
-        while (true) {
-
-            if (!$this->isValid()) {
+        try {
 
+            // Really sorry about the silence operator, seems like I have no
+            // choice. See:
+            //
+            // https://bugs.php.net/bug.php?id=64230
+            if (!@$this->read()) {
                 $errors = libxml_get_errors();
-
+                libxml_clear_errors();
                 if ($errors) {
-                    libxml_clear_errors();
-                    if (!is_null($elementMap)) {
-                        $this->popContext();
-                    }
                     throw new LibXMLException($errors);
                 }
+                throw new ParseException('This should never happen (famous last words)');
             }
 
-            switch ($this->nodeType) {
-                case self::ELEMENT :
-                    $elements[] = $this->parseCurrentElement();
-                    break;
-                case self::TEXT :
-                case self::CDATA :
-                    $text .= $this->value;
-                    $this->read();
-                    break;
-                case self::END_ELEMENT :
-                    // Ensuring we are moving the cursor after the end element.
-                    $this->read();
-                    break 2;
-                case self::NONE :
-                    if (!is_null($elementMap)) {
-                        $this->popContext();
+            while (true) {
+
+                if (!$this->isValid()) {
+
+                    $errors = libxml_get_errors();
+
+                    if ($errors) {
+                        libxml_clear_errors();
+                        throw new LibXMLException($errors);
                     }
-                    throw new ParseException('We hit the end of the document prematurely. This likely means that some parser "eats" too many elements. Do not attempt to continue parsing.');
-                default :
-                    // Advance to the next element
-                    $this->read();
-                    break;
+                }
+
+                switch ($this->nodeType) {
+                    case self::ELEMENT :
+                        $elements[] = $this->parseCurrentElement();
+                        break;
+                    case self::TEXT :
+                    case self::CDATA :
+                        $text .= $this->value;
+                        $this->read();
+                        break;
+                    case self::END_ELEMENT :
+                        // Ensuring we are moving the cursor after the end element.
+                        $this->read();
+                        break 2;
+                    case self::NONE :
+                        throw new ParseException('We hit the end of the document prematurely. This likely means that some parser "eats" too many elements. Do not attempt to continue parsing.');
+                    default :
+                        // Advance to the next element
+                        $this->read();
+                        break;
+                }
+
             }
 
-        }
+        } finally {
+
+            if (!is_null($elementMap)) {
+                $this->popContext();
+            }
 
-        if (!is_null($elementMap)) {
-            $this->popContext();
         }
         return ($elements ? $elements : $text);
 
@@ -304,7 +310,7 @@ class Reader extends XMLReader {
 
         $deserializer = $this->elementMap[$name];
         if (is_subclass_of($deserializer, 'Sabre\\Xml\\XmlDeserializable')) {
-            return [ $deserializer, 'xmlDeserialize' ];
+            return [$deserializer, 'xmlDeserialize'];
         }
 
         if (is_callable($deserializer)) {
diff --git a/vendor/sabre/xml/lib/Version.php b/vendor/sabre/xml/lib/Version.php
index f199e7158..7edb40d67 100644
--- a/vendor/sabre/xml/lib/Version.php
+++ b/vendor/sabre/xml/lib/Version.php
@@ -14,6 +14,6 @@ class Version {
     /**
      * Full version number
      */
-    const VERSION = '1.4.1';
+    const VERSION = '1.5.0';
 
 }
diff --git a/vendor/sabre/xml/lib/Writer.php b/vendor/sabre/xml/lib/Writer.php
index adfbe0cb0..09d4cb321 100644
--- a/vendor/sabre/xml/lib/Writer.php
+++ b/vendor/sabre/xml/lib/Writer.php
@@ -127,7 +127,7 @@ class Writer extends XMLWriter {
 
             if (array_key_exists($namespace, $this->namespaceMap)) {
                 $result = $this->startElementNS(
-                    $this->namespaceMap[$namespace] === '' ?  null : $this->namespaceMap[$namespace],
+                    $this->namespaceMap[$namespace] === '' ? null : $this->namespaceMap[$namespace],
                     $localName,
                     null
                 );