Adds kitty.c/kitty.h implementing the kitty graphics protocol behind
KITTY_GRAPHICS_PATCH, enabled in patches.h.
Supports transmission (direct, file, temp file, POSIX shared memory),
the RGB/RGBA/PNG formats with a self-contained PNG decoder, zlib
compression, chunked transfers, placements with source rects, scaling,
cell offsets, z-index ordering with alpha blending via XRender,
relative and Unicode-placeholder virtual placements, the full set of
delete selectors, queries, image numbers and animation (frame
transfer, composition and playback).
The Makefile used to suppress output (by using @), so this target made sense at
the time.
But the Makefile should be simple and make debugging with less abstractions or
fancy printing. The Makefile was made verbose and doesn't hide the build
output, so remove this target.
Prompted by a question on the mailing list about the options target.
ref.
https://git.suckless.org/st/commit/eb3b894f4076f2b25afc644a1f444b5cbd96aae8.html
