Update git submodules

Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Converted vPing to leverage the object-oriented SNAPS library."
  - Converted vPing to leverage the object-oriented SNAPS library.

    JIRA: FUNCTEST-577

    1. Replaced procedural openstack_utils with the object-oriented SNAPS
       library
    2. Tests now clean themselves up.
    3. Improved code documentation.
    4. Removed dependency on file-based Cirros image and now leveraging the
       download URL.
    5. Removed hardcoded location to the testcases.yaml file to leverage
       the value in config_functest.yaml
    6. Included optional flavor metadata based on the scenario being tested
    7. Included support for multi-part images.
    8. Added enhanced support for configurable images. see SNAPS-76

    Fixed line length verification problem with the previous submission
    Fixed retrieval of external network name to be dynamic.
    Changed external network name retrieval to leverage the newly merged
    snap_util.get_ext_net_name() function
    Added the creation and deletion of flavors.
    SNAPS now has the ability to add/remove security groups from running instances.
    Changed VMInstance constructor by moving userdata to configuration object.

    Change-Id: I0ef5e268eb153d696bb4d9a7533f780e5c603d26
    Signed-off-by: spisarski <s.pisarski@cablelabs.com>