Needs to check luac is 5.3 before running

[take-cheeze]

Sometimes luac isn't 5.3.

golua/lua/state.go

Line 305 in cd7e06d

cmd := exec.Command("luac", "-o", tmp, "-")

[artob]

This function (State.load()) seems the weakest part of the current implementation in general. When attempting to use the library on Android (via GoMobile), the creation of a temporary directory/file fails due to permission denied, unsurprisingly. And, of course, there is no luac binary available even if the previous did succeed.