Socket activated docker

I think socket-proxyd is the way.

Worth reading: https://github.com/dockerlisbon/group/issues/8

follow this: https://github.com/coreos/rocket/issues/106

Created by: davidstrauss

Hi, I'm the author of socket-proxyd. Please let me know if you have any questions.

@davidstrauss I actually found time and did a POC :) https://microblog.pierre-o.fr/2016/testing-socket-activation-with-docker-compose