Add permissions to administer PRLP

Making this change will break existing installations. Can you please include a migration that assigns this new permission to all existing users that have the "administer users" permission?

Not sure patch #2 will break anything. Anyway, site administrators still get access to PRLP settings.

And in my case, this patch is useful because I don't want users with the permission "administer users" to be able to manage PRLP Settings. And in my case, when i give the permission "adminsiter users" I didn't want to give them the permision to manage PRLP settings. So In my mind patch #2 should be committed, not #5 which ensure that an unwanted situation is still present.

Otherwise RTBC++ (#2 or #5)

Turned into MR against 2.0.x branch.

Fixed up tests to use new permission. Cleanup on tests to avoid doing extra work which isn't tested or needed.

Tests are green all round.