Feature request: docker manifest pull

Please provide a new subcommand "docker manifest pull"

I have 2 docker servers (not in a cluster). An "amd64" and a "armhf". I want to make an image on every server locally and then merge them in a manifest list. I can create and push a manifest list on the first server, but when I want to add the second image on the second server, I can't retrieve the already existing list. I only can create a new list. When I currently push this new list, I am losing the first entry.

"docker image pull" gets the image, not the manifest. I would suggest that "docker manifest pull" will pull the manifest and not the image. My workflow would then be:

# on the amd64 server:
docker build -t user/name:tag-amd64 .
docker push user/name:tag-amd64
docker manifest create user/name:tag user/name:tag-amd64
docker manifest push user/name:tag

# on the second armhf server:
docker build -t user/name:tag-armhf .
docker push user/name:tag-armhf
docker manifest pull user/name:tag # <= new subcommand.
docker manifest create user/name:tag user/name:tag-armhf
docker manifest push user/name:tag

Review the existing docker manifest create and docker manifest push command paths, then determine how a remote manifest list should be retrieved and represented locally. Done means docker manifest pull user/name:tag preserves the existing entries so another architecture can be added and pushed without losing them.