Looks like we've been stuck on Emscripten fastcomp backend, misssing out on all new optimisations between LLVM 6 and LLVM 11 and going via slow asm.js pipeline when building.
This changes Docker images for Emscripten projects to point to emscripten-upstream instead and commits the updated artifacts.
* Adding chroma subsampling for mozjpeg
* Adding separate chroma quality.
* Preact sometimes removes the inline styles, this fixes it.
* Simplifying chroma subsample
* Adding comments
* Switching to embind
* Adding options to mozjpeg wasm
* Updating packages
* Ditching enum - causing more problems than it's worth
* Adding mozjpeg options UI
* Forgot about this enum
* Bools just work