Compatibility improvements: remove zsh and graceful errors if sound fails

[krs013]

What it says in the title. WSL had cryptic float errors if libpulse0 wasn't installed, now the sound module will report an error and revert to emulating the sound.

Also replaced zsh in makefile with find. This should be available on all Unix systems as far as I know.

[Baekalfen]

I rebased your code so we don't have the merge commit, and the extra commit, that fixes logging in the first. Also, I removed the self.device = 0, as that isn't need (if it was, we should have added it in the error case above it).

[krs013]

Sounds good, and sorry for the messy history. I appreciate the changes

self.device = 0 was just there so the module doesn't leave __init__() with that field undeclared, but that's more of a tidiness thing than functional. It might lead to errors that won't show up in Python but will in CPython/PyPy. If there's a better place to put it, that's fine--we could even have it initialized to 0 before calling SDL_Init and leave it at that. Not a big deal either way once we remove SDL code from sound.py, which is still something I intend to do to match how we did lcd.py.

[Baekalfen]

It might lead to errors that won't show up in Python but will in CPython/PyPy

I checked. All uses are protected by if self.enabled, so it won't be a problem.

It would be awesome if you have time to move the SDL2 stuff out, like you say.