Switch to side-by-side view

--- a/website/credits.html
+++ b/website/credits.html
@@ -25,7 +25,7 @@
 <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">User manual</a></li>
 <li><a href="index.html#support">Support</a></li>
 
       </ul>