support luvi's compile flag

[Bilal2453]

As of luvit/luvi#276 Luvi can compile Lua sources into bytecode and/or strip debugging symbols from the compiled bytecode. Would be nice if lit make exposed those flags, potentially also adding a package.lua field to control the defaults.

[truemedian]

Luvi can compile Lua sources into bytecode

This is problematic with lit make because lit make allows you to replace luvi, which may not necessarily be bytecode-compatible with the luvi inside lit.

[SinisterRectus]

#252
#263

[Bilal2453]

I do remember this problem yes. Though I think it should be solved instead of being removed completely. The most obvious solution would be to just error at build time if the specified luvi version/flavor is different, combined with this feature being off by default instead of on should eliminate those issues.