As for `ps`, `images`, `network ls` and `volume ls`, this makes it
possible to define a custom default format.
Signed-off-by: Vincent Demeester <vincent@sbr.pm>
Allows the user to use `pretty` as the format string.
This enables users to put custom format options into their CLI config
just like is supported for `docker ps` and `docker images`
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Vincent Demeester