Add a --cidfile flag to podman rm/stop to pass a container ID via a
file. Podman run already provides the functionaly to store the ID
in a specified file which we now complete with rm/stop. This allows
for a better life-cycle management in systemd services. Note that
--cdifile can be specified multiple times to rm/stop.
Signed-off-by: Valentin Rothberg <rothberg@redhat.com>