trigger setSizes in VideoPlayer on Ox.Fullscreen, add Ox.Fullscreen.available to check if fullscreen support is present(i.e. in iframe)

source/Ox.UI/js/Core/Fullscreen.js

@@ -85,6 +85,10 @@ Ox.Fullscreen = (function() {
         });        
     }
 
+    that.available = document.fullscreenEnabled
+            || document.webkitFullscreenEnabled
+            || document.mozFullScreenEnabled || false;
+
     that.bind = function(event, handler) {
         bind(event, handler);
     };
@@ -136,4 +140,4 @@ Ox.Fullscreen = (function() {
 
     return that;
 
-}());
+}());