Favorite functionality put into plugin (not done yet)

Now we have to fix any code in the core which directly uses the Fave class
or any other favorite stuff, since it is pluginised and thus might not be
available on some installations.

lib/default.php

@@ -294,6 +294,7 @@ $default =
         array('core' => array(
                             'AuthCrypt' => array(),
                             'Cronish' => array(),
+                            'Favorite' => array(),
                             'LRDD' => array(),
                             'StrictTransportSecurity' => array(),
                         ),