add open left btn for aside example

src/components/aside/examples/basic/index.html

@@ -29,4 +29,8 @@
       Side menu!
     </ion-aside>
   </ion-aside-parent>
+  <div class="content">
+    <button class="button" (click)="openLeft()">
+      Open Left Menu
+    </button>
 </aside-app>

src/components/aside/examples/basic/main.js

@@ -9,6 +9,9 @@ import {Template, Component, bootstrap} from 'angular2/angular2';
   inline: `<content></content>`,
   directives: [Aside, AsideParent]
 })
-class AsideApp {}
+class AsideApp {
+  openLeft() {
+  }
+}
 
 bootstrap(AsideApp);