adding new user registration form

[y3pio]

PR Summary

Adds a new user registration form/view

Details

• Addressing New user registration #100
• Adds a new user registration form.
  • Linked from nav bar + login page.
• Removes the admin password from the README.
  • Addresses: Remove admin account for Heroku on README.md file #141
• Does NOT* include updates to the app to use admin users for categorizers: Modify code to use the django admin page instead of the Categorizers table #132 -- This will be addressed in a followup PR.

Testing/QA

• Tested on local database

Screen.Recording.2025-02-05.at.4.28.14.PM.mov