title: ng-model for `<input type="file"/>` (with directive DEMO)
body: <p>I tried to use ng-model on input tag with type file:</p>
  
  <pre><code>&lt;input type="file" ng-model="vm.uploadme" /&gt;
  </code></pre>
  
  <p>But after selecting a file, in controller, $scope.vm.uploadme is still undefined.</p>
  
  <p>How do I get the selected file in my controller?</p>