Allows a hubot to subscribe to a Rocket.chat streamer and react when the streamer emits events
const StreamListener = require('hubot-rocketchat-listener')
const listener = new StreamListener(
robot, // hubot instance
'stream-user-events', // stream to listen on
'afterCreateUser', // the particular event name we want to listen for
(user) => { console.log(`User ${user.name} just joined`) } // callback for event
)
listener.listen()