Server-side rollback can take advantage of the rollback-specific update
parameters, instead of being treated as a normal update that happens to
go back to a previous version of the spec.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
This adds support for placement preferences in Swarm services.
- Convert PlacementPreferences between GRPC API and HTTP API
- Add --placement-pref, --placement-pref-add and --placement-pref-rm to CLI
- Add support for placement preferences in service inspect --pretty
- Add integration test
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>