Fix remove_event_handler logic which wasn't working properly,
Allow to use wildcard-removal of registered events.
The remove_event_handler fixes and features are hanging around since August.
They are well tested and now even useful for the checklist destroy method within the checklist performance fixes in PR too.
The remove_event_handler fixes and features are hanging around since August. They are well tested and now even useful for the checklist destroy method within the checklist performance fixes in PR too.