half-shaved calc example works!

[Chris Hibbert <hibbert>]

I've now gotten the "far side of the wire" half of shaving the calc
example to work.  The test program in calcu.cxx dies while cleaning
up; it's attempting to delete the Calc it was using throughout the
test.  It's already succeeded in so many message sends across the wire
that I'm going to declare victory.

If anyone wants to figure out why it dies in the delete, (it's the
fourth line from the bottom of .../calc/calcu.cxx) I'll be glad to
help, but there are too many garbage collection details for me to
grasp at this point.

There is still one case MarkM pointed out that I need to check before
being sure this scheme works:  the constructors of my message
descriptions need to be able to distinguish between overloaded
messages by casting the pointer to member function.  Once I've taken
care of that, I can go on to the "near side of the wire" half, and
when that works, I can fix the stubble script.

Chris