change the wiki link

Author: chenxsan

vimperator/locale/en-US/tutorial.xml

@@ -325,7 +325,7 @@
     &liberator.appname; has an energetic and growing user base. If you've run into a problem
     that you can't seem to solve with &liberator.appname;, or if you think you might have
     found a bug, please let us know! There is support available on the
-    <link topic="https://github.com/vimperator/vimperator-labs/wiki">wiki</link>
+    <link topic="https://github.com/vimperator/vimperator-labs/issues">wiki</link>
     or in the <link topic="irc://irc.freenode.net/vimperator">#vimperator</link> IRC
     channel on <link topic="http://freenode.net/">freenode</link>.
 </p>