In socket.io-client 0.9.1 client side heartbeat was implemented, but tornadio2 doesn't send it in xhr-polling transport

[denya]

In socket.io-client 0.9.1 client side hearbeat was implmeneted, see commit socketio/socket.io-client@0bcd25f

It took heartbeat invetrval and waiting for packet. If not heartbeat -- it triggers reconnect.

But i found, that tornadio2 doesn't start hearbeat process when use xhr-transport.

So we got regular reconnection process.
It's not problem, i can use 0.9.0, but need to fix (may be in clientside library?)