LU-2420 tests: Have POSIX testing on b2_1

LU-2420 tests: Have POSIX testing on b2_1

Have POSIX testing automated on b2_1 as it is on master.
LU-2274 port is included to change the baseline filesystem to ext3
for POSIX testing on SLES distro.

Test-Parameters: envdefinitions=SLOW=yes clientdistro=sles11 testlist=posix
Signed-off-by: Liu Ying <emoly.liu@intel.com>
Change-Id: If20262a37d77053bda3a1e143d74c4ebd11b7ec5
Reviewed-on: http://review.whamcloud.com/4731
Reviewed-by: Jian Yu <jian.yu@intel.com>
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>