Add a missing comma
Always normalize JSON from the official registry

Without removing the check against the repository name the API response
wouldn't be normalized (at least for `dockerfile/rabbitmq`), and
I'd get an exception because Centurion wasn't getting the format
it expected.

At least for my use case this resolves the issue, although I've not
got enough experience to do any real testing for other use cases.
Merge pull request #61 from jellybob/fix-syntax-error

Add a missing comma