If configs are declared for a service and pointing on an old
daemon, error out properly (instead of "page not found").
If there is no configs declared, don't call convertServiceConfigObjs
to avoid having an error.
Signed-off-by: Vincent Demeester <vincent@sbr.pm>
(cherry picked from commit cf5550c426)
Signed-off-by: Eli Uriegas <eli.uriegas@docker.com>