Replace consul with zetcd

[thomasvincent]

The work has been done to integrate consul with Kubernetes but it isn't apparent if the PR is going to be integrated into Kubernetes. If a configuration is selected to deploy both Mesos and Kubernetes then we will use zetcd instead of consul.

https://coreos.com/blog/introducing-zetcd
kubernetes/kubernetes#1957
kubernetes/enhancements#172
kubernetes/kubernetes#31622

[thomasvincent]

Kubernetes team is stating they are focusing on stability not features for the next several sprints. I am going to make a fork and look at integrating with zetcd.

Conversation is here:
kubernetes/kubernetes#31622 (comment)

related issues
kubernetes/kubernetes#1957
kubernetes/kubernetes#10439

[Theaxiom]

This is not going to happen for 1.x Mantl.