update doc

en/classloader.html

@@ -410,6 +410,8 @@ load class success.
   });
 </script>
 
+<script type="text/javascript" src="https://s4.cnzz.com/z_stat.php?id=1279151497&web_id=1279151497"></script>
+
 <script>
   var _hmt = _hmt || [];
   (function() {