Fixes #14181 - Validate registry URL and attempt login
In order to avoid users trying to create containers in an externalregistry that doesn't exist, we should provide some preventativemeasures.
Fixes #12681 - Support rubocop 0.35.1 by fixing broken rules
Fixes #9901 - Better handling of errors in container api
Fixes #10029 - Docker registry API
Fixes #9310, #9518 - Create containers using katello repos
This commit adds code to create Containers using katello repos.
Fixes #9643 - Added search param to the containers index API
Fixes #7874 - Docker Containers API
Routes are namespaced, code still needs to be namespaced