hdf5

[svn-r17725] Bug fix:
There was a mixed use of $RUNTEST and $RUNTESTS. Both of them
meant for the same thing, the launching command of executables.
$RUNTEST was used from the beginning (old v1.4.* versions used
$RUNTEST). Somehow, v1.8 started to use $RUNTESTS and this was
later propogated back to v1.6.8 and on.

After discussing with Mike M., we agree to use the original
$RUNTEST.

test: Up. (before the fix, I could not propage a launch command
into test/h5repack's "gmake check". After the fix, I could.