title: Valdr with UI-select required not updating
body: <p>I am using ui-select with valdr. I used the following directive to patch the name attribute issue and the valdr for ui-select worked, but the when I change the ui-select value its not updating the message. That is the form element remains in ng-invalid state. Same thing works for other inputs that ain't using ui-select.</p>
  
  <p>This is my directive:</p>
  
  <pre><code>angular.module('app').directive('input', function () {
      var count = 0;
      return {
        restrict: 'E',
        compile: function () {
          return {
            pre: function (scope, element, attrs) {
              // if the input is created by ui-select and has ng-model
              if(element.hasClass('ui-select-search') &amp;&amp; attrs.ngModel) {
                var nameAttr = element.parent('.ui-select-bootstrap').attr('name');
                var idAttr = element.parent('.ui-select-bootstrap').attr('id');
                if(nameAttr){
                  attrs.$set('name', nameAttr);
                }
  
                if(idAttr){
                  attrs.$set('id', idAttr);
                }
  
              }
            }
          }
        }
      }
    });
  </code></pre>