Tests: Removed links to tests that no longer exist

Closes jquerygh-1709

Author: peter-lyons-kehl

tests/visual/index.html

@@ -25,12 +25,6 @@ <h2>addClass</h2>
 			<li><a href="addClass/queue.html">Queue</a></li>
 		</ul>
 
-		<h2>Button</h2>
-		<ul>
-			<li><a href="button/button.html">General</a></li>
-			<li><a href="button/performance.html">Performance</a></li>
-		</ul>
-
 		<h2>Checkboxradio</h2>
 		<ul>
 			<li><a href="checkboxradio/checkboxradio.html">General</a></li>