--group-add was used for specifying groups for both service create
and service update. For create it was confusing since we don't have
an existing set of groups. Instead I added --group to create, and
moved --group-add to service update only, like --group-rm
This deals with issue 27646
Signed-off-by: Lily Guo <lily.guo@docker.com>
Update flag documentation
Specify that --group, --group-add and --groupd-rm refers to
supplementary user groups
Signed-off-by: Lily Guo <lily.guo@docker.com>
Fix docs for groups and update completion scripts
Signed-off-by: Lily Guo <lily.guo@docker.com>