Merge pull request #2509 from tw0517tw/patch-1

stop prepend /# before id when no namespace

Author: rauchg

lib/socket.js

@@ -59,7 +59,7 @@ function Socket(nsp, client){
   this.nsp = nsp;
   this.server = nsp.server;
   this.adapter = this.nsp.adapter;
-  this.id = nsp.name + '#' + client.id;
+  this.id = nsp.name !== '/' ? nsp.name + '#' + client.id : client.id;
   this.client = client;
   this.conn = client.conn;
   this.rooms = {};