Add ReactShallowRenderer types

See http://facebook.github.io/react/docs/test-utils.html#shallow-rendering

react/react-addons-global.d.ts

@@ -179,6 +179,8 @@ declare module React {
         findRenderedComponentWithType<C extends Component<any, any>>(
             tree: Component<any, any>,
             type: ComponentClass<any>): C;
+
+        createRenderer(): ShallowRenderer;
     }
 
     interface SyntheticEventData {
@@ -255,5 +257,11 @@ declare module React {
         touchStart: EventSimulator;
         wheel: EventSimulator;
     }
+
+    class ShallowRenderer {
+        getRenderOutput<C extends Component<any, any>>(): C;
+        render(element: ReactElement<any>, context?: any): void;
+        unmount(): void;
+    }
 }