fix(disqus): move to head

_layouts/post.html

@@ -19,15 +19,6 @@ layout: default
 
   {% include share.html %}
   <div id="disqus_thread"></div>
-  <script type="text/javascript">
-      var disqus_shortname = 'dibaiee';
-
-      (function() {
-          var dsq = document.createElement('script'); dsq.type = 'text/javascript'; dsq.async = true;
-          dsq.src = '//' + disqus_shortname + '.disqus.com/embed.js';
-          (document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(dsq);
-      })();
-  </script>
 
   <script src="/js/heading-links.js"></script>
 </div>