Add functional testing for swarm cluster

Gerrit topic: https://review.openstack.org/#q,topic:bp/swarm-functional-testing,n,z

Addressed by: https://review.openstack.org/221633
    Add function testing case for creating swarm bay

Addressed by: https://review.openstack.org/223907
    Functional: Split python client functional testing case

Addressed by: https://review.openstack.org/225212
    WIP: Add Functional Tests for mesos cluster

Addressed by: https://review.openstack.org/226125
    Add functional test cases(containers actions) for swarm

Addressed by: https://review.openstack.org/232421
    Functional: Add testcase of tls_enabled bay creation case.

Addressed by: https://review.openstack.org/241505
    split out k8s and api functional testing

Addressed by: https://review.openstack.org/242687
    WIP: Record diagnostic info from bay nodes

Addressed by: https://review.openstack.org/244389
    Swarm: Add TimeoutStartSec=0 to docker service

Addressed by: https://review.openstack.org/245121
    Functional: Add container creation/deletion on swarm bay.

Gerrit topic: https://review.openstack.org/#q,topic:bp/swarm-high-availability,n,z

Addressed by: https://review.openstack.org/249522
    Functional: Use Magnum client to test container actions on Swarm bay

Addressed by: https://review.openstack.org/252281
    Functional: Raise Exception if bay created failed.

Addressed by: https://review.openstack.org/251869
    WIP: Functional: only copy logs on exception