title: Broken ngModel on Radio buttons with an ngRepeat
body: <p>Plunk: <a href="http://plnkr.co/edit/Y4ntAj2fIIpexKjkCvlD?p=preview" rel="nofollow">http://plnkr.co/edit/Y4ntAj2fIIpexKjkCvlD?p=preview</a></p>
  
  <p>I'm trying to build a form component which allows the user to create multiple instances of a certain data field, but populate them from the same set of inputs.</p>
  
  <p>I'm creating a radio button for each of the items within the set, using <code>ng-repeat</code> then each radio button has its value set to the <code>$index</code> from the repeat. The radio buttons are modelled on <code>$scope.selectedItem</code>, which is used to point the inputs to the right item.</p>
  
  <p>For some reason, however, <code>selectedItem</code> never changes, even though the selected state of the radio buttons do.</p>
  
  <p>I tried a similar thing with static radio buttons and it worked fine, which leads me to believe that there is a problem with <code>ng-model</code> within <code>ng-repeat</code>.</p>