This container can be pulled via:
  docker pull registry.opensuse.org/home/jeff_mahoney/containers/opensuse_tumbleweed/opensuse/server/mail/dovecot:2.4
  docker pull registry.opensuse.org/home/jeff_mahoney/containers/opensuse_tumbleweed/opensuse/server/mail/dovecot:2.4.5
  docker pull registry.opensuse.org/home/jeff_mahoney/containers/opensuse_tumbleweed/opensuse/server/mail/dovecot:2.4.5-3.1
  docker pull registry.opensuse.org/home/jeff_mahoney/containers/opensuse_tumbleweed/opensuse/server/mail/dovecot:latest

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.