This parameter controls the order of operations when rolling out an
update task. Either the old task is stopped before starting the new one,
or the new task is started first, and the running tasks will briefly
overlap.
This commit adds Rollout to the API, and --update-order / --rollback-order
flags to the CLI.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
Upstream-commit: e434a91221
Component: cli
bf4beaf856