Underlying Ansible role for Docker containers

merges variables from four sources:

• service_base_defaults: defined in this role (compose_hull)
• service_defaults: defined in the particular service role
• service_defaults_all: defined top-level
• service_cfg: defined in the playbook

• name
• directory: the directory under which all the configuration etc. of the service will be stored.
• owner: name of the user that should own the service directories
• create_dirs: list of (sub-)directories to create for the service
• port: port of the service (in the container)
• domain: the domain of the service. e.g. 'myservice.example.com'
• external: whether the service should be externally accessible (or only from within the local network)
• traefik: whether to use traefik
• watchtower: whether to use watchtower
• autoheal: whether to use autoheal

• started
• restarted
• recreated
• stopped
• absent