cad20c759f
On the server v0.4.21 has introduced a better way of dealing with intra-stack networking: if the user can specify a list of endpoints exposed internally, we now can setup a ClusterIP for this to avoid the pitfalls of DNS-based load balancing. This exposes the feature using the "Expose" compose field, and adds an extra x-internal-service-type field to explicitly define how intra-stack networking is handled on a service. Signed-off-by: Simon Ferquel <simon.ferquel@docker.com>