update versions menu

Author: Jaime Melis

source/_templates/versions.html

@@ -3,9 +3,7 @@
         <b>{{ version|e }}</b><b class="caret"></b>
     </a>
     <ul class="dropdown-menu globaltoc">
-        <li><a href="/4.8">4.8</a></li>
-        <li><a href="/4.6">4.6</a></li>
-        <li><a href="/4.4">4.4</a></li>
-        <li><a href="http://archives.opennebula.org/documentation:archives">Older Versions</a></li>
+        <li><a href="/stable">Last Stable</a></li>
+        <li><a href="http://opennebula.org/documentation/archives/">Previous Releases</a></li>
     </ul>
 </li>