title: add and remove items between arrays in angular
body: <p>Using an angular array how do I add and remove elements between the two arrays?
  I have <code>$scope.results</code> and <code>$scope.list</code> the results array is the result of a call to a WebAPI and i'm allowing the user to select the elements they want to add to the second array. How do i add from the first to the second and remove from the first at the same time? </p>
  
  <pre><code>    angular.forEach($scope.results, function (item) {
          if (item.selected) {
              $scope.list.push(item);
              //CODE TO REMOVE item from $scope.results here.
          };
      });
  </code></pre>
  
  <p>Additionally if i did a second search and tried to add the same member from the first array to my second array (which already had this user) how do i prevent adding duplicates to the second array (list)?<img src="https://i.stack.imgur.com/HIiP7.png" alt="enter image description here">.</p>
  
  <p>below is a sample of the objects im wanted to transfer between the arrays. the id field is the indicator of uniqueness.</p>