reverted to old tree, unlocked

[Luka <luka@MIT.EDU>]

been at this nearly 7 hours and there's *some* problem
with the new tree i can't nail down.  so i've restored
the old tree and you can consider it back in business.

i'm going to continue messing with this unintrusively
to see if i can figure out what's actually happening
(it's a runtime failure when i try to build and test,
on what otherwise seems like a successful export/re-
import/clean-checkout), and then perhaps schedule
another attempt at the export/import again.

but for now, back as we were.

-pl