[sepia] ceph-ci containers

Hi everyone, I'd really like to push this through and get something working this week. After poking around it seems clear that there aren't any other registries we should be using for our temp/test builds (unless we just spam dockerhub, but that seems unwise). So, let's just get over ourselves and run our own registry. 1- Where to put it? I'm assuming this should go in the same place that chacra is putting our other temp builds. This is in RDU, right? What machine(s) should we use? If we use the same retention policy as the debs/rpms then this will be an incremental increase in the storage needed. 2- What registry software to use? We don't need any fancy featuers whatsoever--just the ability to push, pull, and delete images. So, whatever is easiest to set up. 3- Jenkins integration. I think we need to have a child job linked to the centos build to do the ceph-container build and then push. Similarly, whatever it is that removes the old packages from the repos needs to also delete the image. 4- Chacra/shaman integration? Should the container build show up in shaman/chacra as well? Is there extra work needed to do that? Thanks! sage