Update SDK

Update SDK

docs: a little further clarification on how things work

fix: correct ReadButtons() to use proper mode for co-op multiplayer

all: refactor and separate code, plus add docs

gopher: transparent background

config: set desired author_id

license: put under MIT

all: further refactoring for clarity

docs: add a minimal README

main: improve timing to show title screen, ajust positioning of titles

wall: make opening a little bigger to make game play possible

move walls faster

Fix refresh rate

all: some refactoring for readability