[tlbuild] 2010 builds

[Karl Berry]

I hope that we will start doing builds for TL 2010 earlier than last
year.  And finish earlier, too.  To that end, could those of you who
have not done builds since the 2009 release give the current sources a
try, and report any problems on your respective platforms?

The main changes at this point are in the build system (thanks to peb),
and it would be nice to work on those problems before updating the
engines, etc.

Thanks,
karl