Add /var/lib/cni to kubelet

Necessary to persist this directory for host-local IPAM used by Canal
Add pre-upgrade task to copy /var/lib/cni out of old kubelet.

roles/kubernetes/node/templates/kubelet-container.j2

@@ -21,6 +21,7 @@
   -v {{ docker_daemon_graph }}:/var/lib/docker:rw \
   -v /var/log:/var/log:rw \
   -v /var/lib/kubelet:/var/lib/kubelet:shared \
+  -v /var/lib/cni:/var/lib/cni:shared \
   -v /var/run:/var/run:rw \
   -v {{kube_config_dir}}:{{kube_config_dir}}:ro \
   {{ hyperkube_image_repo }}:{{ hyperkube_image_tag}} \