Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Make GenericTrafficGen class abstract
    
    GenericTrafficGen class is now an abstract class. Only optional methods
    are implemented.
      - 'run_traffic' and 'terminate' are mandatory.
      - 'listen_traffic', 'verify_traffic' and 'wait_for_instance' are
        optional. By default these methods doesn't execute any action.
    
    JIRA: YARDSTICK-853
    
    Change-Id: I2befdaa337af79cc2364bdd7c66183c31c5ab69a
    Signed-off-by: Rodolfo Alonso Hernandez <rodolfo.alonso.hernandez@intel.com>
    

1 files changed, 0 insertions, 0 deletions

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
-Subproject c22c231d4061ae957d06206922978bfedf3aba7
+Subproject 3636829d1fd2053d09c95a98ec1a697c601e0e6