Add links to the other versions we have in stock.

Doc/tools/sphinxext/indexsidebar.html

             <h3>Download</h3>
             <p><a href="{{ pathto('download') }}">Download these documents</a></p>
+	    <h3>Docs for other versions</h3>
+	    <ul>
+	      <li><a href="http://docs.python.org/2.6/">Python 2.6 (stable)</a></li>
+	      <li><a href="http://docs.python.org/3.0/">Python 3.0 (stable)</a></li>
+	      <li><a href="http://docs.python.org/3.1/">Python 3.1 (in development)</a></li>
+              <li><a href="http://www.python.org/doc/versions/">Old versions</a></li>
+            </ul>
+
             <h3>Other resources</h3>
             <ul>
               {# XXX: many of these should probably be merged in the main docs #}
@@ -13,7 +21,4 @@
               <li><a href="http://wiki.python.org/moin/PythonBooks">Book List</a></li>
               <li><a href="http://www.python.org/doc/av/">Audio/Visual Talks</a></li>
               <li><a href="http://www.python.org/doc/other/">Other Doc Collections</a></li>
-              <li>&nbsp;</li>
-              <li><a href="http://www.python.org/doc/versions/">Previous versions</a></li>
-              <li>&nbsp;</li>
             </ul>