Metric notification breaks on secure bay

[hongbin]

Magnum introduced tls support in swarm bay. We need to incorporate tls support to metric notification modules, in which docker client is used to pull metrics from bay.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/232138

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/232139

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/232138
Committed: https://git.openstack.org/cgit/openstack/magnum/commit/?id=49cf17c12dc18eef5d540388fac9a9fe825f5264
Submitter: Jenkins
Branch: master

commit 49cf17c12dc18eef5d540388fac9a9fe825f5264
Author: Hongbin Lu <email address hidden>
Date: Wed Oct 7 10:38:24 2015 -0400

    Move 'docker_for_container' to a common module

    This method is for obtaining a docker client that is used to
    communicate with a swarm bay. Pulling it out of docker conductor
    allows it to be reused later.

    Change-Id: I495835595ee049103f97ee8b5bfe9eb74fe9ad45
    Partial-Bug: #1503460

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/232139
Committed: https://git.openstack.org/cgit/openstack/magnum/commit/?id=30eacb52c965e3107616431d7567ddb86d3dc080
Submitter: Jenkins
Branch: master

commit 30eacb52c965e3107616431d7567ddb86d3dc080
Author: Hongbin Lu <email address hidden>
Date: Wed Oct 7 14:09:40 2015 -0400

    Pull metrics by using TLS enabled client

    Magnum introduced TLS support in swarm bay, so swarm monitor needs
    to use TLS enabled client to pull data.

    In addition, this commit eliminates data pulling from the docker
    daemon of individual bay nodes, since they are not secured by TLS.
    Instead, we always pull from swarm. Due to that, additional text
    parsing is needed, since the output of docker.info from swarm is
    not well formed.

    Change-Id: I121bfa98622c240d5c777901794a35c0d8990345
    Closes-Bug: #1503460