updated select2 to latest version (v4.0.7)

bower_components/select2/src/js/jquery.select2.js

@@ -3,8 +3,9 @@ define([
   'jquery-mousewheel',
 
   './select2/core',
-  './select2/defaults'
-], function ($, _, Select2, Defaults) {
+  './select2/defaults',
+  './select2/utils'
+], function ($, _, Select2, Defaults, Utils) {
   if ($.fn.select2 == null) {
     // All methods that should return the element
     var thisMethods = ['open', 'close', 'destroy'];
@@ -25,7 +26,7 @@ define([
         var args = Array.prototype.slice.call(arguments, 1);
 
         this.each(function () {
-          var instance = $(this).data('select2');
+          var instance = Utils.GetData(this, 'select2');
 
           if (instance == null && window.console && console.error) {
             console.error(