These are moved:
* Display -> busdisplay.BusDisplay
* FourWire -> fourwire.FourWire
* EPaperDisplay -> epaperdisplay.EPaperDisplay
* I2CDisplay -> i2cdisplaybus.I2CDisplayBus
`paralleldisplay` is now `paralleldisplaybus` (and registered as
`paralleldisplay` too).
Bus related helpers are split out of display_core into bus_core.
It is in still displayio since it is a dependency of both
busdisplay and epaperdisplay.
Fixes#7667
the backlight situation will be revisited with the next board prototype,
but it's good to prove this can be done.
Depends on https://github.com/adafruit/esp32-camera/pull/6 which should
be merged before this.
this gives us a comfortable few hundred kB flash space left for the app
1398912 bytes used, 763776 bytes free in flash firmware space out of 2162688 bytes (2112.0kB).
