fix topics link

Author: kkung

application/templates/base.html

@@ -28,7 +28,7 @@ <h3><a href="http://langdev.org">LangDev</a></h3>
         <ul class="nav">
           <li><a href="http://langdev.org/posts/">Forum</a></li>
           <li><a href="http://log.langdev.org/">Log</a></li>
-          <li><a href="http://topics.langdev.org/posts/">Topics</a></li>
+          <li><a href="http://topics.langdev.org/">Topics</a></li>
           <li class="active"><a href="http://links.langdev.org/">Links</a></li>
           <li><a href="http://docs.langdev.org/">Docs</a></li>
         </ul>