Primarily motivated to get almost everything out of globals and fix
issue #631. This is a stripped-down version of the gist there without
the memory debugging and reboot-into-direct-boot mode.
Mostly move things to functions. Clean up some dead code and comments.
I think the biggest win is not actually the PicoGraphics framebuffer,
which is well-behaved, but random temporary floats that were leaking
previously.
Also type-annotated and lints clean.
Fixes#631. (As much as I think is possible.)
I decided I wanted the first chevron a little smaller, and realized I had the sign of the chevron height value reversed. The initial white triangle is now a bit smaller, and the chevron stripes slightly wider.
* correct filename in name_badge.py for Tufty
* Update 240x240 round breakout examples to work with PicoGraphics
* Update colourlcd240x240demo.py to work with PicoGraphics
* Fixed rainbow.py for Pico Display and Pico Display 2.0
* Update display examples to work with PicoGraphics
* add new display example 🌈
* adventures in rainbow RAM
* add button example for pico inky pack
* tidy up examples, make names more consistent
* Update Pico Explorer and 160x80 LCD breakout examples
* Accommodate dither
LionsPhil