Use zig assert for apicheck

[natecraddock]

Using a zig assert for apicheck enables stack traces for panics.

TODO:

• Lua 5.5 changed how LUA_USE_APICHECK works and I cannot find a way to define lua_assert correctly
• Not working for luajit yet. Haven't looked closely

[natecraddock]

It's looking like it might not be possible to get this working in Lua 5.5 currently.

Other versions of Lua work like this:

1. The user.h file creates this define #define luai_apicheck(l,e) zlua_assert(e)
2. luai_apicheck is later used in the definition of lua_assert

Lua 5.5 removed luai_apicheck. If you try to define lua_assert in the user h file, a later import from lapi.h unconditionally defines lua_assert which overrides the custom one from the user h file.

I tried patching the lapi.h header file to remove those definitions, but since headers are searched for in directories I couldn't find a way to exclude the original unpatched lapi.h. Maybe copy all of the other headers and the patched header to a new directory?

I'm considering posting on the Lua mailing list about this change in behavior in Lua 5.5 and see what comes up

[robbielyman]

@natecraddock looking through the source, I suspect one can do

#undefine LUA_USE_APICHECK
#define api_check(l,e,msg)     zlua_assert(l,e,msg)

hmmm... apparently not...