LU-358 tests: Add the branch and commit-id to the yml.

LU-358 tests: Add the branch and commit-id to the yml.

yaml.sh updated to provide the information requested in the JIRA the
change is simple and requires that LUSTRE_BRANCH and LUSTRE_REVISION
are defined, if they are not defined then the elements are left blank

Change-Id: Ie558660bdf9cde4290342ea4e807ed22fa42d32a
Signed-off-by: Chris Gearing <chris@whamcloud.com>
Reviewed-on: http://review.whamcloud.com/1629
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Minh Diep <minh.diep@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>