title: ERROR on Populate RadAutoCompleteTextViewComponent
body: <p>I got the error bellow on trying to populate a RadAutoCompleteTextView.
  Any hint in regard?</p>
  
  <p>Many thanks in advance</p>
  
  <pre><code>@ViewChild("rankingsCtrl", { static: false }) rankingsCtrl: RadAutoCompleteTextViewComponent;
  
  
  this.rankingsCtrl.autoCompleteTextView.insertTokenAtIndex(new TokenModel("Test",""), 0);
  
  
  JS: ERROR Error: Uncaught (in promise): TypeError: Cannot read property 'addTokenModelAt' of undefined
  JS: TypeError: Cannot read property 'addTokenModelAt' of undefined
  JS:     at RadAutoCompleteTextView.push.../node_modules/nativescript-ui-autocomplete/ui-autocomplete.js.RadAutoCompleteTextView.insertTokenAtIndex (file:///node_modules/nativescript-ui-autocomplete/ui-autocomplete.js:589:0)
  </code></pre>