Auto-register users and populate their attributes via LDAP durning authentication

[phebal]

I don't think we need to store users' NetID in db, but maybe we should? I can use the email from LDAP to find the user in the database. However we'd need to disallow setting custom emails in user profile (obvious security hole.) What do you think @fenekku?

Auto-verify user's email.

Part of #1

[fenekku]

NetIds are specific to Northwestern University, right? So I am not a big fan of storing them in our own database/creating a special use case unless there is a clear way to make this generalizable to everyone or it is a custom extension.

On the security implications, if we enforce email verification i.e. the user changes his/her email, we send them a verification token at their new address and they must click on it before we link them to their Netid or what have you, would that work?