I'd like to "clone" a repository and then sync from the origin while applying a filter. For example, let's say I have a repo called "upstream" which will serve as the origin. I'd like to create a new repo called "testing" that pulls everything from upstream with the exception of rpms that match "kernel-*". Is such a workflow currently supported in pulp (2.1)? If so, what's the best way to achieve it? Create an empty repo with no --feed and use copy operations? Or create a repo whose --feed url is that of my local copy of "upstream"?