Speed up Sprite rotation on an ESP32
Update utf8 serial decoder to handle illegal format strings
Remove need for D0_USED_FOR_xx (issue #271)
Clean up setup files
Correct various comment typos
Fixed bug where wrong wodth was returned for 1bpp Sprite
Improved speed for copying a 1bpp Sprite into another 1bpp Sprite (
affects Sprite pushImage() function only)
Added option to setup for colour inversion
Bodmer