[WIP] Notifications (#599)

Adds a new notifications feature to the Admin plugin. It will now lookup notifications which are set up on getgrav.org and will inform users, and also alert for new updates and provide awareness on various topics.

Also fixes issue with Array field in `value_only` mode, improperly displaying the key when novalue was set, and fixes issue with drag handlers in Array not showing/hiding properly (#950)

Updated FontAwesome to 4.6.3

vendor/zendframework/zendxml/library/ZendXml/Exception/ExceptionInterface.php

@@ -0,0 +1,14 @@
+<?php
+/**
+ * Zend Framework (http://framework.zend.com/)
+ *
+ * @link      http://github.com/zendframework/zf2 for the canonical source repository
+ * @copyright Copyright (c) 2005-2014 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license   http://framework.zend.com/license/new-bsd New BSD License
+ */
+
+namespace ZendXml\Exception;
+
+interface ExceptionInterface
+{
+}