Fix "binary file log matches" error (#124)
Fix "binary file log matches" error (#124)

grep sometimes believes that the main log output
file is a binary file, which stops processing
of the failed/killed output at the end of the
test run.  Use grep -a to make sure log
output is processed as text.

Signed-off-by: bunder2015 <8895d4710d634bf3eedbb49460627c10b2e5d1b0@gmail.com>
zfsonlinux/zfs-buildbot,zfsonlinux/zfs-buildbot,gmelikov/zfs-buildbot,gmelikov/zfs-buildbot