Introduce languages options to ULS

Default value of this option will be $.uls.data.autonyms().
It can be set to limit language selection to a set of languages.

Updated examples, used a config variable wgULSLanguages to set this.

Change-Id: Ia322cbdcdb14f08619d2e4df5b23e2702841d147

src/jquery.uls.data.utils.js

@@ -47,6 +47,20 @@
 		return ( $.uls.data.languages[language] && $.uls.data.languages[language][2] ) || language;
 	};
 
+	/**
+	 * Returns all language codes and corresponding autonyms
+	 * @return array
+	 */
+	$.uls.data.autonyms = function() {
+		var autonymsByCode = {};
+
+		for ( var language in $.uls.data.languages ) {
+			autonymsByCode[language] = $.uls.data.autonym( language );
+		}
+
+		return autonymsByCode;
+	};
+
 	/**
 	 * Returns an array of all region codes.
 	 * @return array