[qmtest] Patches for scheduler updates

[Mark Mitchell]

> when running with process parallelism
> then lots and lots of things don't work.  Like, most but not all of
> the regression tests fail, and it's not immediately obvious to me why.

They fail because QMTest doesn't compute the correct path to itself the
second time it is invoked.  (It would be nice if UNIX, like Windows,
would give you a way to get at the path to the executable that is
running.)

The qmtest shell script was not correctly handling having both QM_HOME
and QM_BUILD set.

I'll check in the combined set of fixes shortly.

-- 
Mark Mitchell
CodeSourcery, LLC
mark at codesourcery.com