[Dev-luatex] multiple interpreters

[Taco Hoekwater]

Hi,

In a moment or so, I will upload a new version that can have
multiple lua interpreters. My current syntax is extremely minimal:

   \lua<int>{<lua stuff>}
   \latelua<int>{<lua stuff>}

So, just like before but with an extra integer, just like the
\marks syntax. Non-existing interpreters are auto-initialized.
There is no provision (yet?) to "clean up" an interpreter.
WDYT?

Taco