mainly doing this as the pure rust zstd backend doesn't accept discohawk produced chd files, although they are completely valid by reference zstd implemetation standards, max_perf uses the reference zstd here
this gives us a great level of control over how we build SDL2, omitting parts we don't want, and including parts we do want, like libusb support!
windows sdl2 normally doesn't support libusb, but with some magic it can be built and linked in fairly easily, giving windows sdl2 libusb support.
libusb support in sdl2 means official GC adapter support! (resolves#1879)
linux build will be done in a later commit
Also fix up libbizhash so it builds on clang
Slight fixes to sameboy and msxhawk makefiles
Fix rcheevo submodule commit (no actual changes, just make it point to a commit upstream actually has)
SDL2 .so not yet rebuilt, need to consider how to do that
citra seems to need at least Debian 11 to build
libe_sqlite3.so seemed to have already been built with Debian 10 so not bothering touching that
libwaterboxhost.so is Rust / targets glibc 2.28 anyways, nothing needs to be done there
Add in liblua-* variant for Linux lua library names (resolves#3678)
Remove some more unused NLua code
Make LuaState internal, we don't need to see it (NLua.Lua API slightly changed to accommodate this, tests could be broken due to this?)
Make various other NLua classes internal, we don't need to see them
Check against lua library loading failing, provide a non-fatal message box if it has failed instead of crashing on some exception.
Remove UnixSearchPaths (unneeded with LD_LIBRARY_PATH being set) and unused IImportResolvers
I'm pretty sure all the existing instances were intended to use `default(T)` if
the key isn't present, except maybe the cheatcode converters but I don't care to
rewrite those at the moment
Cleanup this code so it plays nicer with BizHawk's "run everything on the main thread" (+ WinForms not playing nice with async methods)
Resend any game session start / achievement unlocks / leaderboard triggers if they failed. Wait for all achievement unlocks and leaderboard triggers to finish on Dispose() (mostly for catching them when user closes BizHawk)
Update rcheevos to 10.7.0
YoshiRulz