Try adding disqus for documentation

doc/misc/footer.html

@@ -7,3 +7,21 @@
   </ul>
 </div>
 <!--END GENERATE_TREEVIEW-->
+<script type="text/javascript">
+    /* * * CONFIGURATION VARIABLES * * */
+    var disqus_shortname = 'rapidjson-doc';
+    
+    /* * * DON'T EDIT BELOW THIS LINE * * */
+    (function() {
+	    var dt = document.createElement('div');
+	    dt.id = "disqus_thread";
+	    (document.getElementsByClassName('contents')[0]).appendChild(dt);
+
+        var dsq = document.createElement('script'); dsq.type = 'text/javascript'; dsq.async = true;
+        dsq.src = 'http://' + disqus_shortname + '.disqus.com/embed.js';
+        (document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(dsq);
+    })();
+</script>
+
+</body>
+</html>