virtual machine tests

[Tom Tromey <tromey at redhat dot com>]

I've been doing some surgery on the VM parts of libgcj, and it occurs
to me that there isn't really a comprehensive test suite for this.  I
think it is time to set one up.

My current plan is to make a new Mauve module called "vm", and put
tests there.  Of the many test frameworks we have at the moment, I
find jacks is the easiest to work with (and most appropriate for this
kind of testing), so I think I will just copy that framework and use
it.  Eventually I'd like to move the verifier tests here as well.

It will be a little while before I set this up for real.  Send email
if you have an objection or comment.

Tom