Automatically configure display size based on CIRCUITPY_DISPLAY_WIDTH

[relic-se]

This update allows request_display_config to automatically configure the display to the user's preference (as determined by CIRCUITPY_DISPLAY_WIDTH) if a specific size is not provided. It also allows the user to provide a desired width and automatically determine the appropriate display height.

These changes are based on the implementation in Fruit-Jam-OS (adafruit/Fruit-Jam-OS#44) and hopefully could add uniformity to applications based in that ecosystem which support multiple display sizes rather than implementing this functionality independently.

[FoamyGuy]

One request to update docs with info about this. Looks good to me otherwise.

[relic-se]

My typical usage for this function now is the following:

from adafruit_fruitjam.peripherals import request_display_size
try:
    request_display_size()  # user display configuration
except ValueError:  # invalid user config or no user config provided
    request_display_size(720, 400)  # default display size

I think this is acceptable, but would you rather add another argument to default to the user configuration if provided? Ie: request_display_size(720, 400, use_default=True).

[FoamyGuy]

I think it's goodas-is with None being used as the signal to use defaults from settings.toml.

[FoamyGuy]

Thank you! this looks good to me