Vban-cmd

This update introduces some breaking changes:

Changed

- `strip[i].comp` now references StripComp class
- To change the comp knob you should now use the property `strip[i].comp.knob`
- `strip[i].gate` now references StripGate class

- To change the gate knob you should now use the property `strip[i].gate.knob`

- `bus[i].eq` now references BusEQ class

- To set bus[i].{eq,eq_ab} as before you should now use bus[i].eq.on and bus[i].eq.ab

- new error class `VBANCMDConnectionError` raised when a connection fails or times out.

There are other non-breaking changes:

Changed

- now using a producer thread to send events to the updater thread.
- factory.request_vbancmd_obj simply raises a `VBANCMDError` if passed an incorrect kind.
- module level loggers implemented (with class loggers as child loggers)

Added

- `strip[i].eq` added to PhysicalStrip

Added

- Connection section to README.

Changed

- now using clear_dirty() when sync enabled.

Fixed

- bug in set_rt() where multiple commands sent in single request packet.
- bug in apply where index was sent twice.

Added

- ability to read conn info from vban.toml config

Changed

- assume a vban.toml in examples. README's modified.

Added

- fadeto(), fadeby() methods added to strip/bus classes.
- OBS example added.

Changed

- Event class add/remove now accept iterables.
- property setters added to Event class.
- ldirty logic moved into VbanRtPacket class.
- in util, threshold a level is considered dirty moved to 7200 (-72.0)
- now print bus levels in observer example.

Fixed

- initialize comps in updater thread. fixes bug when switching to a kind before any level updates

Changed

- Logging module used in place of print statements across the interface.
- base error name changed (VBANCMDError)

Fixed

- Timeout and raise connection error when socket connection fails.
- Bug in observer example

Added

- tomli/tomllib compatibility layer to support python 3.10