Freeze Break Request - eu-central-1 for fedimg

[Ralph Bean]

I've got this patch lined up to add a new region to fedimg's workload.  We
haven't been uploading images to eu-central-1, but we should be.  If it ends up
being problematic, we can always revert the commit and push the old config back
out.

I talked it over with dgilmore this afternoon and we shouldn't need to make any
further changes in the AWS console for this.

This is for:

- https://github.com/fedora-infra/fedimg/issues/36
- https://fedorahosted.org/rel-eng/ticket/6259