Hi.  I have pushed the attached patch.  It should be completely
backwards compatible, or there is a bug, so please test this.  It adds
two new variables to allow both developers and users to influence the
valgrind options used.  You may want to re-read the manual, I updated it
to assume people use the parallel automake test harness today.

Developers may want to use 'LOG_COMPILER=$(LOG_VALGRIND)' instead of
'LOG_COMPILER=$(VALGRIND)' in your Makefile.am, to make it easier for
end-users to modify the options passed to valgrind.  The old style still
works fine, and in the same way as before.  The reason for the change is
to enable end-users to be able to change VALGRINDFLAGS during a 'make
check' phase if they want.

/Simon