LU-1082 test: create test for mds-survey

LU-1082 test: create test for mds-survey

Create a mds-survey.sh test with two test cases
1. test without stripe count
2. test with stripe count
Create test_224[a|b] for quick run on metadata survey

Notice, we remove all clients before testing
because the real client and echo_client share
the same client object memory

Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Change-Id: I453ac34d8b6019e109be5d89d482300d31571f93
Reviewed-on: http://review.whamcloud.com/2156
Tested-by: Hudson
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>