Spinner: Add spinner to visual tests index page

Author: jzaefferer

tests/visual/index.html

@@ -43,6 +43,7 @@ <h2>Widgets</h2>
 	<li><a href="dialog/dialog.html">Dialog</a></li>
 	<li><a href="progressbar/progressbar.html">Progressbar</a></li>
 	<li><a href="slider/slider.html">Slider</a></li>
+	<li><a href="spinner/spinner.html">Spinner</a></li>
 	<li><a href="tabs/tabs.html">Tabs</a></li>
 </ul>