[#28] Adds user registration
Created by: AlanLiu96
Resolves #28 (closed)
- Makes changes to sign_up form
- Overrides RegistrationsController for Devise
- Adds test to ensure registration succeeds
While it may not ultimately be necessary in the final application, it makes user creation easier both for our own testing, and forms a part of user creation for other issues (#6 (closed))