Added Signup Endpoint

[ryanjung1998]

No testing created yet

[Axeloooo]

To Do @ryanjung1998

• Make sure you are up to date with the dev branch
• Hash the password using the bcrypt dependency
• Create a session in the req.session.user field
• Return a status code of 201
• Create tests for your implementation under the authentication.test.ts file
• Validate the existence of the cookie found in the response.header["set-cookie"][0] field from response after a test request using the http object was sent