title: Detecting cell changes in angular.js and ng-grid
body: <p>I've racked my brain but am unable to figure out how to detect the cell data change in ng-grid.
  The following snippet is using ng-change which does correctly call save(), but it's not the 
  trigger I want since it gets called for any keyed entry. I need to know when the editing of
  the cell is complete.</p>
  
  <p>Any help would be appreciated.</p>
  
  <pre><code>angular.module('controllers', ['ngGrid']).
  controller('ContactsListCtrl', ['$scope', 'Contacts', function ($scope, Contacts) {
      var editableCellTemplate = '&lt;input type="text" ng-class="\'colt\' + col.index" ng-input="COL_FIELD" ng-model="COL_FIELD" ng-change="save()"/&gt;';
  
      Contacts.get(function(data) {
          $scope.contacts = data;
  
      });
      $scope.gridOptions = {
          data: 'contacts',
          enableCellSelection: true,
          enableRowSelection: false,
          enableCellEdit: true,
          showSelectionCheckbox: true,
          columnDefs: [
              {field: 'lastName', displayName: 'Last Name', enableCellEdit: true, editableCellTemplate: editableCellTemplate},
              {field: 'firstName', displayName: 'First Name', enableCellEdit: true, editableCellTemplate: editableCellTemplate},
              {field: 'email', displayName: 'EMail Address', enableCellEdit: true, editableCellTemplate: editableCellTemplate},
              {field: 'phone', displayName: 'Phone', enableCellEdit: true, editableCellTemplate: editableCellTemplate}
          ]
      };
      $scope.save = function() {
          $scope.contact = this.row.entity;
          Contacts.save($scope.contact);
      }
  }]);
  </code></pre>