Merge pull request angular-ui#112 from alexmahu/OptgroupInit

Fixed angular-ui#57 - now select2 initializes also for optgroup

Author: ProLoser

src/select2.js

@@ -22,7 +22,7 @@ angular.module('ui.select2', []).value('uiSelect2Config', {}).directive('uiSelec
 
       // Enable watching of the options dataset if in use
       if (tElm.is('select')) {
-        repeatOption = tElm.find('option[ng-repeat], option[data-ng-repeat]');
+        repeatOption = tElm.find( 'optgroup[ng-repeat], optgroup[data-ng-repeat], option[ng-repeat], option[data-ng-repeat]');
 
         if (repeatOption.length) {
           repeatAttr = repeatOption.attr('ng-repeat') || repeatOption.attr('data-ng-repeat');