Add support for GLua

[SenseiHiraku]

Hey there,
I wanted to propose adding support for GLua (Garry's Mod Lua), which is basically LuaJIT with extended support for some c-operators.

The non-standard symbols are the following:

        "continue",
        "&&",
        "||",
        "!=",
        "!",
        "//",
        "/**/"

I'd also be satisfied if these symbols just convert to the standard-lua syntax (with the exception of continue, which has no equivalent)

[SenseiHiraku]

As for the linked fivem documentation in #855, here is the gmod one:
https://wiki.facepunch.com/gmod/Specific_Operators