Configure method for ongoing discovery of apiserver by kubelet

[emmanuel]

Need a method for kubelet to find kube-apiserver, in a way that allows the kube-apiserver to move among hosts.

[emmanuel]

Options for the discovery part:

1. Use an additional private IP. Distribute a private IP to all instances running kubelet, then attach the IP as a secondary private IP to the host that ends up running the kube-apiserver.
2. Use an internal ELB between the kubelet and the kube-apiserver.
3. Use VPC-private DNS and register the host that kube-apiserver lands on at a pre-shared address (e.g., $STACK_NAME-kube-apiserver.example.com).
4. Use SkyDNS, either on every host, just services hosts, or just one host. If not global, then some additional method of following DNS servers will be needed (EIP, ELB).