Update git submodules

Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Update Functest to OpenStack stable/pike"
  - Update Functest to OpenStack stable/pike

    It updates setup.py, (test-)requirement.txt and upper-constraints.txt
    according to OpenStack requirements [1].

    It disables all Features testcases as they are not synchronized with
    OpenStack stable/pike yet [2].

    The docker functest-parser is simplified as it can be based on
    functest-core as both Functest and Parser leverage on OpenStack
    stable/pike.

    ODL_TAG and REFSTACK_TAG variables are set to master again.

    [1] http://git.openstack.org/cgit/openstack/requirements/log/?h=stable/pike
    [2] https://wiki.opnfv.org/display/functest/Requirements+management

    Change-Id: I23fa84f35244c1f4026abd89414b99576f042ee4
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>