[lltx] luaotfload update

[Khaled Hosny]

Hello list,

I managed to finish the long due syncing of luaotfload with ConTeXt,
in the unstable branch:
https://github.com/khaledhosny/luaotfload/tree/unstable

and updated fontspec as well:
https://github.com/wspr/fontspec/tree/otfl-unstable

There are many internal changes in this update which would break any
package depending on internal lua interfaces, also bugs and breakage are
highly probable. I did some basic testing, but more testing are
welcomed.

In this update too the support for non-standard features were dropped,
namely tlig & trep (AKA TeX ligatures) and anum (was anybody using
this?). Hans no longer includes that code in his "plain variant" from
which luaotfload is derived, and even when he did only -- and --- were
supported and I had to patch it to add the rest. Someone have to
convince Hans to implement this in the "plain variant" or implement it
himself, I don't really need this feature myself.

Also loading of OFM fonts is now broken, I don't feel like debugging
this and I doubt anyone is using them, but the above applies here too.

Finally, if someone can put this on tlcontrib, this would be great.

Regards,
 Khaled

-- 
 Khaled Hosny
 Egyptian
 Arab