Add user roles or permissions

[reeveng]

Is your feature request related to a problem? Please describe.

there should be a catalogue of permissions which can be configured on a per user / per action (maybe)
or 2 to 3 kind of user roles, 1 default for everyone, 1 moderator, and 1 contributor?
think about it long and hard, will have lasting effects, permissions are more easily configurable, but with every new users, needs new configuration, how many users will be able to become a contributor etc?

Describe the solution you'd like

just a way so some people can adjust puzzles of users who contributed them, but stopped and the puzzles need some fixing