Switch to side-by-side view

--- a/website/devel.html
+++ b/website/devel.html
@@ -23,7 +23,7 @@
 	<li><a href="index.html">Home</a></li>
 	<li><a href="pics/index.html">Screenshots</a></li>
 	<li><a href="download.html">Downloads</a></li>
-	<li><a href="usermanual/index.html">User manual</a></li>
+	<li><a href="doc.html">Documentation</a></li>
       </ul>
     </div>