LU-1024 tests: Test replay-vbr.test_1c failed

LU-1024 tests: Test replay-vbr.test_1c failed

Fixed execution of runmultiop_bg_pause from replay-vbr.sh.

The test-framework.sh wasn't able to to be included in
runmultiop_bg_from script, because since it was started via sh
and dirname didn't return correct path for LUSTRE initialization.

Running the script as executable allows to detect it's directory
correctly via dirname.

Xyratex-bug-id: MRP-299
Reviewed-by: Alexander Zarochentsev <alexander_zarochentsev@xyratex.com>
Reviewed-by: Andriy Skulysh <Andriy_Skulysh@xyratex.com>
Signed-off-by: Kyrylo Shatskyy <kyrylo_shatskyy@xyratex.com>
Change-Id: I0c1e88af405a87bf73ff3e2ac438bccba2b92afc
Reviewed-on: http://review.whamcloud.com/2003
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Li Wei <liwei@whamcloud.com>
Reviewed-by: Yu Jian <yujian@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>