- make sure we set flag in changes when config var changed
- move current deck get/set into backend
- set_config() now returns a bool indicating whether a change was
made, so other operations can be gated off it
- active decks generation is deferred until sched.reset()
- QueueConfig is only used by the scheduler
- DeckConfig was being used in places that Config should have been used
- Add "Dict" to the name so that the bare name is free for use with a
stronger type.