title: Socket.IO 1.0.x: Get socket by id
body: <p>In the 0.9.x version, we can get socket by ID like this:</p>
  
  <pre><code>io.sockets.socket(socketId)
  </code></pre>
  
  <p>But in 1.0.x we can't. How to find a socket by id in 1.0.x?</p>