os-*-* tools should be containerised

[yuanying]

os-*-* tools only run from packages at this moment.
it causes that software deployment resource (which is heat resource) doesn't work on micro os (such as atomic or coreos).

we want to use software deployment resource in our heat templates to build bay.
so we need containerized os-*-* tools.

[Steven Hardy (shardy)]

Note we already implemented an approach where the required os-* tools are built into a "agent container" image, that is then deployed and used to deploy subsequent containers:

https://github.com/openstack/heat-templates/tree/master/hot/software-config/heat-container-agent

https://github.com/openstack/heat-templates/blob/master/hot/software-config/boot-config/templates/install_container_agent.yaml

The basic approach is to use cloud-init to start the agent container on boot, then heat drives all subsequent launching of containers via the os-* tools running in the agent container.

We used a somewhat modified version of this to implement containerized compute services on TripleO compute nodes, so the basic approach is proven:

https://github.com/openstack/tripleo-heat-templates/tree/master/docker

[Spyros Trigazis (strigazi)]

I did an effort to use alpine linux. The compressed image size is 33mb and uncompressed 111mb.

Can someone test:
https://hub.docker.com/r/strigazi/heat-container-agent/tags/