This makes it possible to delegate snapshots key management to the
server, and to reclaim the responsibility.
Signed-off-by: Ying Li <ying.li@docker.com>
This lists any matching keys, and requires the user to pick which one
to choose, if there is more than 1 matching key. Also requires the
user to confirm before deleting.
Signed-off-by: Ying Li <ying.li@docker.com>