Authentication

[logonoff]

As Amy, Boyan or David, I would like to create an account to be able to keep track of my books and Critters even when using different devices.

Tasks

• [ ] Create back end routes that check user login information against whats in the database

Acceptance criteria

• A user should be able to login if they've provided the correct username and password
• Send the correct response if the username/password is invalid