Killpack/auth *WIP* *WIP* *WIP*

WIP.

It's gonna work like this:
- You type in your username and password, which hits the `authorizations` endpoint. On successful authentication, it returns your auth token.
- Ember stores this auth token somewhere and uses it to make requests from thereon out.
Nope, it's not. What if we have a user whose email address is `COOL_GUY@YAHOO.COM`? In that case, the above method would never be able to find this user, since his email is all uppercase. We need to downcase both of them.