TMI: rustpkg (what else?)

After a fun week of conferencing, I spent today working on implementing RUST_PATH and invoking the default build logic from package scripts (the latter is kind of necessary to make package scripts useful). The second one works now, and it's just a matter of automating the test case. The first one, well, it's not done yet and also the test case deadlocks mysteriously, so I have to sort that out.

I'm hacking from the LA area this week, and my first day back in Mountain View is a week from today.