title: Socket io not broadcasting to specific room
body: <p>I'm trying to broadcast some info to a specific room:</p>
  
  <p><strong>server side</strong></p>
  
  <pre><code>var io = require('socket.io')(server, { path: '/my/path' });
  server.listen(8090, function () {
      console.log("Server ON.");
  });
  
  io.on('connection', function(socket){
      socket.on('room', function(room) { //set the room
          socket.join(room);
          socket.room = room;
      });
      socket.on('new message', function (data) { //receive and broadcast the msg
          socket.broadcast.to(socket.room).emit('new message', data);
      });
  });
  </code></pre>
  
  <p><strong>client side</strong></p>
  
  <pre><code>//initial client config
  var socket = io(URL_SOCKET, {path: '/my/path'});
  socket.emit('room', room_id);
  socket.on('new message', function (data) {
      do_something(data);
  });
  
  function on_change(data){
      socket.emit('new message', data);
  }
  </code></pre>
  
  <p><strong>The problem here is:</strong> the <code>socket.broadcast.to</code> is broadcasting the information sent by clients (by calling <code>on_change</code>) to all the rooms (to everyone). What am I doing wrong?</p>