Tag releases to public docker repository

[bshi]

A recent update (in the past two hours) has brought down our ability to launch new google/docker-registry containers since there is only the 'latest' tag available.

[proppy]

@bshi, yes we had to push a previous version of the image not build from source and in order to do this we had to delete and recreate the repo :(

Which tag are you missing?

[bshi]

We were using latest (since that's the only one I could see was available). I think #38 describes in more detail exactly what I was looking for.