OIDC PR#1 --- Enable/Disable regular Login and Signup

@ mention of reviewers`

@Didayolo @cjh1`

A brief description of the purpose of the changes contained in this PR.

This is PR-1 for changes needed for feature: #1298 (closed)

Platform owners can now enable/disable regular signup and login. This is useful for dedicated instances where people just want Organization authentication rather than using the normal sign in and signup.

• If you disable signup i.e. set ENABLE_SIGN_UP=False in your .env, you will not see sign up button and sign up page
• If you disable sigin i.e. set ENABLE_SIGN_IN=False in your .env, you will see empty login page. This is on purpose because you will see organization authentication buttons there (soon)

Note: if you change either of these variables in your .env you need to stop and start the service:

docker-compose down

docker-compose up -d

Issues this PR resolves

• #1298 (closed) -> Regular signup/signIn

Checklist

• Code review by me
• Hand tested by me
• I'm proud of my work
• Code review by reviewer
• Hand tested by reviewer
• CircleCi tests are passing
• Ready to merge