[lltx] luaotfload maintenance

[Khaled Hosny]

After so many not so successful attempts to sync luaotfload with ConTeXt
font code, I gave up. It is simply to much effort for little (personal)
gain. I was mainly worried about having two incompatible OpenType
implementations, but I'd rather not have my fonts working with LuaLaTeX
at all, than spending all that time an effort.

Any way, the code was just accumulating bugs and no one is working on
it, so, unless someone stands up to maintain that code, I'm going to
declare it unmaintained and essentially an abandonware.

Regards,
 Khaled