Add 'manual' processing of events to track door open/close status for doors that do not have a sensor configured.
As of a first event that represents a door open or close state, the door status will be reported as opened or closed by the `lock_status()` response, instead of the 'unknown' status reported by the panel itself.
This is a bugfix release for 0.0.11, fixing handling of system events (that are not related to a specific door or auxiliary).
**Full Changelog**: https://github.com/vwout/zkaccess-c3-py/compare/0.0.10...0.0.12