Registration page changes

[jbriones1]

Description

The old frontend assumed users would be logging in, which didn't really work out since we don't store this anywhere. For the current iteration of software, we'll be changing this to assume that one server instance is an entire session and there is only ever one admin.

Tasks

• On the registration page, change the dropdown to radio buttons between "Admin" and "Player".
• Remove the name for "Admins", just ask for the password. This also means removing the name from the backend.

[karyao]

Will be moving the "admin" registration from /register to /admin backed with password - due to registering as admin when there's only one admin doesn't make too much sense.