Merge branch 'master' of https://github.com/kubernetes/kubernetes.github.io into release-1.8

* 'master' of https://github.com/kubernetes/kubernetes.github.io:
  Update photon-controller.md (#5279)
  add back Zach and Steve to PR assignment
  fix the command output
  Update troubleshooting.md
  Update guaranteed-scheduling-critical-addon-pods.md
  Include filename fix (#5139)
  k8s-tutorials-stateful-application (#5112)
  Update gce.md (#5163)
  Update stage-documentation-changes.md (#5213)
  fix the command output
  Fix token-authentication-file internal link

docs/tasks/administer-cluster/guaranteed-scheduling-critical-addon-pods.md

@@ -49,6 +49,7 @@ It doesn't have any user facing configuration (component config) or API and can
 ### Marking add-on as critical
 
 To be critical an add-on has to run in `kube-system` namespace (configurable via flag) and
+
 * have the `scheduler.alpha.kubernetes.io/critical-pod` annotation set to empty string, and
 * have the PodSpec's `tolerations` field set to `[{"key":"CriticalAddonsOnly", "operator":"Exists"}]`