[luatex] Proposal to fix the namespace argument

[Karl Berry]

Thank you very much, Taco/Hans/Hartmut.  That is great.

So given these new features, I think for (pdf)lualatex in TL'09 we
should remap at least the non-prefixed primitives to \LaTeX.  (I guess.)
I'm not sure if we should remap the ones that already include "lua" or
start with \U.  I don't see a great need to do so.

For plain, though, I think it's not necessary.  After all, we're not
going to change "tex" itself (ever), and etex/pdftex/etc. will continue
to invoke pdftex in TL'09.  (When and if that ever changes, we
could/should change the ini files to hide the luatex primitives for
those fmt's.)

So for TL'09, the only way that users can invoke plain-with-luatex is by
"luatex" or "pdfluatex".  It seems reasonable to me for those programs
to expose native luatex (whatever it happens to be), with no remapping.

Thoughts?

Reminder to self: we should also communicate our plans, when they are
settled, to Christian.  It would be disastrous if MiKTeX and TL did
different things here.