Mock registry store created, auto_create is working

Documented requirement for a simple persistent data store for the Registry

Started to implement device classes code. ...

Simple mocking interface now working.

Method signatures for Registry sketched out

Initial design for enhanced persistent registry done

Some ideas about device registration added

Method signatures for device classes added

Started to flesh out device classes proposed interfaces

Python 3 now supported. ...

Logger now stores apparent power and real power headings.
Logger now stores temperature from eTRV in csv file

Updated device database comments for MIHO002 device

Now displays receive time of incoming messages

Noted the layering of switching between tx/rx might be sub optimal

Fine tuned settings when sharing MiHome and legacy devices

Renamed new radio2 module as radio, and removed old code

Removed any remaining spi-direct and tidied the build process. ...

Tested monitor.py, switch.py and legacy.py on Raspberry Pi.
All work from the same driver now.

Removed legacy direct-to-SPI interface. ...

This code now does FSK tx/rx and OOK tx from the same driver.

Tested FSK tx and rx on Pi, works fine ...

Tested both monitor.py and switch.py

Fixed compile typos. ...

Build test done on mac

Simplified the choice between len and cbp receive

Updated TODO list for next steps of radio.c

Implemented radio.c/radio_get_payload ...

Not yet tested

Implemented a better HRF_readfifo_burst. ...

This has facilities to read a fixed payload, or a count byte preceeded payload.

Framework for FSK receive in place

Started working through new FSK receiver architecture

Tested with MiHome adaptor plus, new FSK transmitter works fine

FSK Transmit coded, ready for test

Restructured switch.py so we have a tx-only test. ...

This is in preparation for pushing the FSK transmitter into radio.c

Refactored so that we can create a tx-only switch loop tester. ...

This will be useful for integrating a new FSK transmitter without receiver

Tested on Raspberry Pi, switch, monitor, and legacy work with spi scaffold

radio2.py offers temporary spi interface for radio.py ...

Tested on mac only.