Doco(317 templates): fix #1663 example of merged cells

Author: PaulL1

misc/tutorial/317_custom_templates.ngdoc

@@ -15,6 +15,8 @@ In this example we create a grid almost the same as the most basic one, but with
 with a cellTemplate that totals all the items above it in the grid.  This template continues to work when the data is 
 filtered or sorted.
 
+The custom row template merges all the cells together when the entity.merge value is true.
+
 You can use [grid.appScope](/docs/#/tutorial/305_appScope) in your row template to access
 elements in your controller's scope. More details are on
 the [scopes](/docs/#/tutorial/305_appScope) tutorial.
@@ -40,7 +42,8 @@ In the cellTemplate you have access to `grid`, `row` and `column`, which allows
           $interval.cancel(sec);
           $scope.wait = '';
           return '<div ng-class="{ \'my-css-class\': grid.appScope.rowFormatter( row ) }">' +
-                     '  <div ng-repeat="(colRenderIndex, col) in colContainer.renderedColumns track by col.colDef.name" class="ui-grid-cell" ng-class="{ \'ui-grid-row-header-cell\': col.isRowHeader }"  ui-grid-cell></div>' +
+                     '  <div ng-if="row.entity.merge">{{row.entity.title}}</div>' +
+                     '  <div ng-if="!row.entity.merge" ng-repeat="(colRenderIndex, col) in colContainer.renderedColumns track by col.colDef.name" class="ui-grid-cell" ng-class="{ \'ui-grid-row-header-cell\': col.isRowHeader }"  ui-grid-cell></div>' +
                      '</div>';
         }, 6000);
       }
@@ -57,6 +60,10 @@ In the cellTemplate you have access to `grid`, `row` and `column`, which allows
           data.forEach( function(row, index) {
             row.widgets = index % 10;
           });
+          data[1].merge = true;
+          data[1].title = "A merged row";
+          data[4].merge = true;
+          data[4].title = "Another merged row";
           $scope.data = data;
         });