User Registration

[mattrrubino]

Give users the ability to register for hidemysecretsauce!

• Create frontend HTML registration form
• Serve form from Flask endpoint /signup
• Validate form data from Flask endpoint /signup
• Store authentication information in MongoDB database

Flask:
https://flask.palletsprojects.com/en/2.1.x/
https://flask.palletsprojects.com/en/2.1.x/patterns/wtforms/

PyMongo:
https://www.mongodb.com/blog/post/getting-started-with-python-and-mongodb
https://www.w3schools.com/python/python_mongodb_getstarted.asp
https://pymongo.readthedocs.io/en/stable/