title: ngTable with Checkboxes not select all the check boxes on the grid
body: <p>How can I select all check boxes on the grid when I click the top check box.At this moment it clicks only the current page check boxes.If you can simulate your solution on Plunk,it's highly appreciate.Thanks in advance.</p>
  
  <p>Here is the link : <a href="http://plnkr.co/edit/EAShRt?p=preview" rel="noreferrer">Table with checkboxes</a></p>
  
  <pre><code>$scope.checkboxes = { 'checked': false, items: {} };
  
  // watch for check all checkbox
  $scope.$watch('checkboxes.checked', function(value) {
      angular.forEach($scope.users, function(item) {
          if (angular.isDefined(item.id)) {
              $scope.checkboxes.items[item.id] = value;
          }
      });
  });
  </code></pre>