Add address_little_endian for epaper displays with little endian
(low byte first) addresses.
Also clears allocated display and display bus memory so it has a
known state. The acep member wasn't always set so it varied
accidentally.
Fixes#7560. May fix#7778. Fixes#5119.
The "scale" parameter wasn't exposed in the library, and there
were some problems in how it was handled.
This also fixes some types in the pixel-drawing functions.
Also, move the rendering setup code to shared-module from
shared-bindings.
In CP 5.0, displayio_display_core_set_region_to_update now starts
its own transaction, so it has to be moved outside of the transaction
started by the render call.