Add ability to access Control Call data

[jm-welch]

I'd like to be able to write a script for Hubot to maintain status of active Control Calls. It looks like the object type to look for is CONF_CALL_STATE_NOTIFY, but I'm uncertain if there are others.

I'm currently using the following within the receiveWS method to start taking a look at the data:

else if data.MESSAGE == "CONF_CALL_STATE_NOTIFY"
  @robot.logger.info msg

... but haven't come up with anything genius as to how to interact with them yet. I'll start tinkering and let folks know what I come up with, but figured I'd start the conversation going at the same time.