Improve Kubernetes docs and tidy up the plugin.
Improve Kubernetes docs and tidy up the plugin.

Some minor code review markups and docs tidying.

alexhersh/calico-kubernetes,Symmetric/calico-kubernetes,projectcalico/calico-kubernetes,projectcalico/calico-kubernetes,alexhersh/calico-kubernetes,Symmetric/calico-kubernetes,caseydavenport/calico-kubernetes,caseydavenport/calico-kubernetes