feat(OpenStack): Add new scripts to support OpenStack OEM handling

Included are scripts to monitor the CoreOS remote etag, as well as
load a new image into a OpenStack Glance image store.
Is there an easy way to grab this information without requiring qemu-img?  Right now curl and python-glanceclient are the only pre-reqs for this.  I'd like to keep it slimmed down as much as possible.  It is optional to leave it out, but if you do the default "micro" size for most providers is a 512MB disk which we fail on (but not till after the boot is attempted).  Putting that value in causes an error at instantiation time which is easier to work with.