title: Socket.io specifying heartbeat
body: <p>I can't seem to find out how to set the heartbeat options for socket.io? I'd love to be able to specify what happens when a "timemout" happens, and when the server hasn't gotten any response from the client for some time.</p>
  
  <p>For some reason the disconnect event isn't always firing, even though it has passed over an hour without the client not being connected. This often happens with the standalone <a href="https://github.com/nkzawa" rel="noreferrer">Java socket.io client</a></p>