Merge branch 'joamag/system-state' into 'master'

CHANGELOG.md

README.md

frontends/libretro/res/boytacean_libretro.info

frontends/libretro/src/lib.rs

frontends/sdl/src/main.rs

frontends/sdl/src/sdl.rs

frontends/web/index.ts

frontends/web/package.json

frontends/web/ts/gb.ts

src/apu.rs

src/cpu.rs

src/gb.rs

src/info.rs

src/lib.rs

src/mmu.rs

src/ppu.rs

src/rom.rs

src/state.rs

src/util.rs