Open Stack

I am happy to report our CentOS 7 AFS mirrors are now live[1]! Today we are only
mirroring extras, os and updates. I don't think we need anything else, but if we
do please let us know.

The neat part of our CentOS mirrors is we still have gpgcheck enabled and using
the RPM-GPG-KEY-CentOS-7 gpgkey. Meaning we are using properly signed RPMs. The
reason we get this is because we are using rsync.

Starting tomorrow, our centos-7 DIBs will enable our new AFS mirrors. I don't
expect an issue, but if there are problems, we'll be able to revert using
nodepool.

Lastly, the only step left to complete is writing a validation script to parse
the repodata files and ensure we've rsync'd all the repo files correctly before
we `vos release mirror.centos` to AFS.  

[1] http://mirror.dfw.rax.openstack.org/centos/7/
[2] https://review.openstack.org/#/c/315162/