Hubot install procedure got changed again
Updates for Hubot 2.4.2+ and other improvements

- Support new Adapter.send() format in Hubot 2.4.2+
- Avoid polluting the user object cache with reply_to data and other junk
- Make robot.messageRoom() and robot.send() easier to use;

    robot.messageRoom "1_blah@conf.hipchat.com", "hi!"

    user = robot.userForName('Some Dude')
    robot.send user: user, "PM by user object!"

    robot.send user: "1_1@chat.hipchat.com", "PM by user jid!"

Fixes #16, fixes #29, fixes #64