Import kubernetes/community docs (#6863)

* Import docs from other repos

* imported test docs

* fix README copy

* Add ToC YAML and index page for imported docs.

* modify update-imported-docs.sh

* Add `imported` to global ToCs

* Add nav to imported section

* remove unnecessary scope for docs/imported

* update script w/ comments and directory root fixes

* use genCmd variable

* display output of generation command

* Update instructions

* Add Community to /docs/imported/index.md

* fix travis errors

* update README.md and fix community docs issues

* simplify code, add comment

* make sure the binary is used instead of `go run`

* add automated handling for links from imported files

update-imported-docs/reference.yml

@@ -0,0 +1,42 @@
+repos:
+- name: kubernetes
+  remote: https://github.com/kubernetes/kubernetes.git
+  branch: release-1.9
+  generate-command: hack/generate-docs.sh
+  files:
+  - src: docs/admin/cloud-controller-manager.md
+    dst: docs/reference/generated/cloud-controller-manager.md
+  - src: docs/admin/kube-apiserver.md
+    dst: docs/reference/generated/kube-apiserver.md
+  - src: docs/admin/kube-controller-manager.md
+    dst: docs/reference/generated/kube-controller-manager.md
+  - src: docs/admin/kubelet.md
+    dst: docs/reference/generated/kubelet.md
+  - src: docs/admin/kube-proxy.md
+    dst: docs/reference/generated/kube-proxy.md
+  - src: docs/admin/kube-scheduler.md
+    dst: docs/reference/generated/kube-scheduler.md
+  - src: docs/user-guide/kubectl/kubectl.md
+    dst: docs/reference/generated/kubectl/kubectl.md
+- name: federation
+  remote: https://github.com/kubernetes/federation.git
+#  # Change this to a release branch when federation has release branches.
+  branch: master
+  generate-command: hack/generate-docs.sh
+  files:
+  - src: docs/admin/federation-apiserver.md
+    dst: docs/reference/generated/federation-apiserver.md
+  - src: docs/admin/federation-controller-manager.md
+    dst: docs/reference/generated/federation-controller-manager.md
+  - src: docs/admin/kubefed_init.md
+    dst: docs/reference/generated/kubefed_init.md
+  - src: docs/admin/kubefed_join.md
+    dst: docs/reference/generated/kubefed_join.md
+  - src: docs/admin/kubefed.md
+    dst: docs/reference/generated/kubefed.md
+  - src: docs/admin/kubefed_options.md
+    dst: docs/reference/generated/kubefed_options.md
+  - src: docs/admin/kubefed_unjoin.md
+    dst: docs/reference/generated/kubefed_unjoin.md
+  - src: docs/admin/kubefed_version.md
+    dst: docs/reference/generated/kubefed_version.md