Draft: fix(handlers): ensure tags are always deleted during a manifest delete
It swaps the order in which we try to delete tags before deleting the manifest.
It also tries to delete any dangling tags for a digest, even if the manifest does not exist. The API will return a 404 only when the manifest's digest doesn't exist and there were no dangling tags associated to the digest either.
Related to #379 (closed)
Edited by Jaime Martinez