fix link to commits

Closes #7

Author: steveschnepp

_layouts/default.html

@@ -44,7 +44,7 @@ <h2>Munin is open-source</h2>
 								</a>
 							</div>
 							<div class="col-xs-6">
-								<a href="https://github.com/munin-monitoring/munin/commits/devel" class="button">
+								<a href="https://github.com/munin-monitoring/munin/commits/" class="button">
 									<i class="mdi mdi-git"></i>
 									<p>Last commits</p>
 								</a>