* Download to delegate and sync files when download_run_once
* Fail on error after saving container image
* Do not set changed status when downloaded container was up to date
* Only sync containers when they are actually required
Previously, non-required images (pull_required=false as
image existed on target host) were synced to the target
hosts. This failed as the image was not downloaded to
the download_delegate and hence was not available for
syncing.
* Sync containers when only missing on some hosts
* Consider images with multiple repo tags
* Enable kubeadm images pull/syncing with download_delegate
* Use kubeadm images list to pull/sync
'kubeadm config images pull' is replaced by collecting the images
list with 'kubeadm config images list' and using the commonly
used method of pull/syncing the images.
* Ensure containers are downloaded and synced for all hosts
* Fix download/syncing when download_delegate is a kubernetes host
