Add reference manifests for using Cilium as the cluster network.

[rktidwell]

This adds manifests for using Cilium as the cluster network. This adjusts the example quick-install manifest for Cilium 1.8. It leverages the cni-install.sh script for convenience to install the Cilium binary on the host. This script also has the side-effect of creating a network configuration for Cilium, which we tell Kubernetes to ignore by simply naming the Multus configuration with a prefix of 02- so that it take precedence.