LU-232 do not use bash variable to pass test setup state between sub-tests

LU-232 do not use bash variable to pass test setup state between sub-tests

Port the patch from bug 22842 attachment 30538 to b1_8 branch:
1) fix sanity tests 42, 101 and 102
2) fix PATH variable to search utilities from $LUSTRE/tests dir first

Signed-off-by: Yu Jian <yujian@whamcloud.com>
Change-Id: Idb58789efc1a1a0a50b54db5cb1f6bad5b5f8daa
Reviewed-on: http://review.whamcloud.com/467
Tested-by: Hudson
Reviewed-by: Chris Gearing <chris@whamcloud.com>
Reviewed-by: Brian J. Murrell <brian@whamcloud.com>
Reviewed-by: Johann Lombardi <johann@whamcloud.com>