This is a pathetically simple entry, since I wasn't able to start until
Sunday afternoon.  Ah, well.  It successfully interacts with the test servers,
and delivers packages by shortest paths. It does *not* take other robots into
account.

It is slightly smarter than the first version about delivery, though, trying
to estimate delivery cost/benefits.

I hereby grant the right to anyone to publish or do whatever they like with
this code.  Have fun.
