LU-3401 tests: make sanity test_27z robust and verbose

LU-3401 tests: make sanity test_27z robust and verbose

* do not depend on positional parameters for most output
* use "lfs getstripe [-c|-i|-s]" options to get specific values
* parse OST index/objid/seq on a line-by-line basis
* dispaly more infomation in error messages

Test-Parameters: envdefinitions=SLOW=yes,ENABLE_QUOTA=yes clientdistro=el6 serverdistro=el6 clientarch=x86_64 serverarch=x86_64 serverjobs=lustre-master serverbuildno=1508 testlist=sanity
Signed-off-by: Bobi Jam <bobijam.xu@intel.com>
Change-Id: Iaf4bbd30a1f9c3bf47d634ddc5e122de60a25776
Reviewed-on: http://review.whamcloud.com/6468
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>