[tlbuild] test builds?

[Karl Berry]

Luigi has committed the last batch of substantive changes to LuaTeX, so
I guess we may as well attempt trial builds. I know many of you already
have, and the autobuilds are happening, but for those still doing
individual builds ...

We shouldn't commit anything yet, though. I hope we'll be able to start
the pretest early, maybe even by the end of this week, but that will
depend on how things go. --thanks, karl.