container/make-manifest-list.py

container/make-manifest-list.py

- don't print command failure in worker; let the caller print them
  if desired (allow silent failure)
- allow for empty tags list
- look for CEPH_SHA1.  GIT_COMMIT was the sha1 of the ceph-container.git
  commit
- change default paths to prerelease
- add --dry-run to avoid final push
- rename 'HOST' to 'CONTAINER_HOST'
- Use ARCH_SPECIFIC_HOST instead of CONTAINER_HOST (which is used by podman)

Signed-off-by: Dan Mick <dan.mick@redhat.com>