Merge pull request #1232 from rsmitty/custom-flags

docs/vars.md

roles/kubernetes/master/defaults/main.yml

...tes/master/templates/manifests/kube-apiserver.manifest.j2

...r/templates/manifests/kube-controller-manager.manifest.j2

...tes/master/templates/manifests/kube-scheduler.manifest.j2

roles/kubernetes/node/defaults/main.yml

roles/kubernetes/node/templates/kubelet.j2