- the subscriber threads captured the loop counter by reference while
the spawning loop kept incrementing it: a genuine data race
- depending on timing, threads could also end up with duplicate
subscriber names; capture the counter by value instead
- Split INITIALIZING state into Init+Bind+Connect
- Remove PAUSE state
- Convert state/transitions to enum classes (CamelCase)
- Transition to a state only once previous handler is complete
- Add CompleteInit transition to notify Initializing state
that config updates are complete
- Deprecate WaitForEndOfState(transition) in favor of
WaitForState(state)/WaitForNextState()
- Update tests/plugins to new APIs
- Deprecate CheckCurrentState() in favor of NewStatePending()
