Add Chat

[nathanmsmith]

We have this really cool chat feature on uclaradio.com:

But our mobile listeners can't chat 😞. That is, until you close this pull request!

This is probably gonna be a pretty big change: you're going to need to mockup and create a new chat view and interface with our website somehow. If you have any questions about how chat works on the site, @hsuregan is the person to ask.