When getting settings from database, running across NULL loads default
setting for given option. Becuase entity unserializer always returned
NULLs instead of FALSEs due to bug in TextHelper, it ended up always
loading default settings (but only after reloading entity, setting it in
the settings page worked correctly until relog).
This fix is closely related to fde6fc2.
- Jobs specify main privilege and sub privileges separately
Rationale: increase maintenance, restrict what can be done runtime
- Renamed ChangeUser* to EditUser* (consistency with EditPost*)
- Simplified enum names and configuration reading
- IJob interface members must be explicitly implemented
Rationale: reduce chances of forgetting something, or typos in
inherited method names
- Invalid privileges names in configuration yield exceptions
