fixed how the GridStack object is obtained

jQuery plugins return the jQuery object, to get the plugin, also in the case of GridStack 0.2.6 (latest) you use the data() method with the correct name

gridstack/gridstack-tests.ts

@@ -10,7 +10,11 @@
 var options = <IGridstackOptions> {
     float: true
 };
-var gridstack:GridStack = $(document).gridstack(options);
+var element: JQuery = $(document).gridstack(options);
+var gridstack: GridStack = $(document).data("gridstack");
+var gsFromElement: GridStack = element.data("gridstack");
+
+if (gridstack !== gsFromElement) throw Error('These should match!');
 
 gridstack.addWidget("test", 1, 2, 3, 4, true);
 gridstack.batchUpdate();

gridstack/index.d.ts

@@ -4,7 +4,8 @@
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 
 interface JQuery {
-    gridstack (options: IGridstackOptions):GridStack
+    gridstack (options: IGridstackOptions): JQuery;
+    data(key: "gridstack"): GridStack;
 }
 
 interface GridStack {