Can't create super users

[stealthrabbi]

A few endpoints rely on the current user being a super user. However, when creating a user, there's no way to specify a user as being a super user, and the DB column defaults to false.

I believe that updating UserBase in the pydantic model to include the superuser field will do it, as well as updating the DB opertions in crud_user.py.

Also, the application has Groups, but they're not actually used.