N°2847 * Update CKeditor to 4.15.1

* Add iTop default languages to ckeditor
* Change CKeditor skin from flat to Moono-Lisa

js/ckeditor/plugins/wsc/dialogs/tmpFrameset.html

@@ -11,7 +11,7 @@ For licensing, see LICENSE.html or http://ckeditor.com/license
 
 function doLoadScript( url )
 {
-	if ( !url )
+	if ( !url || typeof url !== 'string' )
 		return false ;
 
 	var s = document.createElement( "script" ) ;