This commit adds a hidden placeholder of `.Self` for
`docker node ls --format` so that if the node is the same
as the current docker daemon, then a `*` is outputed.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
This fix tries to address the comment https://github.com/docker/docker/pull/30376#discussion_r97465334
where it was not possible to specify `--format` for `docker node ls`. The `--format` flag
is a quite useful flag that could be used in many places such as completion.
This fix implements `--format` for `docker node ls` and add `nodesFormat` in config.json
so that it is possible to specify the output when `docker node ls` is invoked.
Related documentations have been updated.
A set of unit tests have been added.
This fix is related to #30376.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>