Everything else it depends on was already there, and now we have a
somewhat consistent code chain.
Kubernetes-commit: 5649f9a578f4f130f61579d77d5609fbdaf82a1f
Prevent a Kubelet from shutting down when the server isn't responding to
us but we cannot get a new certificate. This allows a cluster to coast
if the master is unresponsive or a node is partitioned and their client
cert expires.
Kubernetes-commit: b3a11aa635022761637090f4fc8d5cb57f3f0010
