[RFC] More user roles

[WithoutPants]

Having users use the shared test account is less than ideal, and I figure that we don't want to open up registration too much.

Propose adding the following user roles:

• FINGERPRINT_READ - allows querying for fingerprints only - plus the minimum operations for the user control panel to work.
• FINGERPRINT_SUBMIT - implies FINGERPRINT_READ, allows for submission of fingerprints.

Propose also that configuration should include default roles when a user registers without an invite code.

In practise, I see envision the following:

• open up free registration without invite code, allowing for fingerprint reading and possibly submitting
• maintain the existing invite code system, which assigns more broader roles

[philpw99]

Can I be one of the submiters?