ld-ac3-decode packaging and deal with sox binary

[oyvindln]

ld-ac3-decode is a separate c++ binary that is called by ld-decode so it's not straight forward to package as part of a python package - might be doable to make a separate pip wheel with py-build-cmake

It also needs sox

there is a static-sox similar to static-ffmpeg which might be usable for sox, otherwise might be easiest to do a custom static build since builds of it has dlls that collide with dlls deps we are already using.