There is a problem when a Thread stops: it destroys all of the modules
that it required. This is because we unconditionally call luax_atexit
when modules are required, and when the thread lua_State dies it takes
all of the modules with it. To fix this, lovr<Module>Init will return
whether or not initialization successfully happened, which provides us
with enough info to know if we should place the luax_atexit destructor