Allow a user to have multiple access tokens
Expand README
Justin doesn't like bad data
Make sure they have either the email or the username
Give two ways to access the user model;

1. Either through the traditional route, via user_id,
2. Or through the user-friendly route, via the username.
Remove whitespace
Add some user model specs
Add some Requests specs
Create user controller
Add users helper stub
Add users spec
Create user with just email
Add skip email check
Remove NULL constraint
Create email spec
Remove null constrant on username