zfstests buildstep should fail if zfs-tests.sh fails (#66)
zfstests buildstep should fail if zfs-tests.sh fails (#66)

bb-tests-zfstests.sh was not accounting for a zfs-tests.sh
failure. Introduce logic to handle cases where zfs-tests.sh
fails and ensure an error code is returned.

Signed-off-by: Giuseppe Di Natale <8f90fd86203578c7bda52281540dd9a2276d6d80@llnl.gov>
zfsonlinux/zfs-buildbot,gmelikov/zfs-buildbot,zfsonlinux/zfs-buildbot,gmelikov/zfs-buildbot