[luatex] New bidi in babel

[Javier Bezos]

I've just published a first version of a new bidi algorithm
for babel. It works with both L and R texts, and it changes
the font if necessary, so that the features are the right
ones (mainly the Script, which is essential in Arabic).

No doubt there are still some issues, so I invite you
to try it out and report errors (and make suggestions).
It's on

https://github.com/latex3/latex2e/tree/master/required/babel

There is a sample file under samples (lua-bidibasic.tex / pdf).

Javier