Repackage to pyproject/toml, port to gpiod/gpiodevice

[Gadgetoid]

Testing:

git clone https://github.com/pimoroni/weatherhat-python -b repackage
cd weatherhat-python
./install.sh --unstable

[thismarty]

Hi, all. Hel Gibbons directed me to this git. I set up this pull on my Pi5 with a WeatherHAT (and Pimoroni NVME drive baseboard) and it seems to work fine. I have it installed in a virtual environment, running the weather.py demo, which appears to be accurrately reading the HAT sensors and rendering the results to the HAT LCD. I've had it runnning for over a day now, nonstop, without issue. Hope this helps!