Use etcd in Kubernetes example, and update to Kubernetes 0.6.

@alainjobart 

The example is working again end-to-end. Other than etcd, most things are better in Kubernetes v0.6 than they were in v0.4. There's even a built-in cluster monitoring console with live graphs and everything!

However, due to the new IP-per-service model, it's gotten more complicated to publish services to the outside world; you have to explicitly give it the public IP address to forward (or tell GCE to generate one as part of a load balancer). For frontend services, that works perfectly, but it's a bit awkward for direct admin access to vtctld and vttablet. We can see what solutions make sense for admin access to Vitess from outside as the Kubernetes networking model matures.