Suggesting author header in translation files

This can be highly useful when a translation need to be updated and you
need to contact an older translator.

select2_locale_en.js.template

@@ -1,5 +1,7 @@
 /**
  * Select2 <Language> translation.
+ * 
+ * Author: Your Name <your@email>
  */
 (function ($) {
     "use strict";