All requests are prefaced by /api.
POST /auth/register registers a user
POST /auth/login logs a user in
PUT /auth/update updates a user's information
DELETE /auth/remove removes a user
GET /users/:user_id/nibbles gets all nibbles from a user with the id of user_id
GET /users/:user_id/nibbles/:_id gets a nibble with populated content
POST /users/:user_id/nibbles/ creates a new nibble
POST /users/:user_id/nibbles/:_id creates a new nibble extending the path of the nibble with the id of _id
PUT /users/:user_id/nibbles/:_id edits the nibble with the id of _id
DELETE /users/:user_id/nibbles/:_id removes the nibble with the id of _id