Add Docker build capability (#9128)

* Add Dockerfile and make commands

* add background run option

* Expand on OSS attribution in new Dockerfile

* Begin adding README instructions for Docker

* Add new stage command

README.md

@@ -16,7 +16,38 @@ For more information about contributing to the Kubernetes documentation, see:
 * [Using Page Templates](http://kubernetes.io/docs/home/contribute/page-templates/)
 * [Documentation Style Guide](http://kubernetes.io/docs/home/contribute/style-guide/)
 
+## Building the site using Docker
+
+If you'd like, you can build the Kubernetes docs using Docker. To get started, build the image locally:
+
+```bash
+$ make docker-image
+
+# The underlying command:
+$ docker build . \
+  --tag kubernetes-hugo \
+  --build-arg HUGO_VERSION=0.40.3
+```
+
+You can create an image for a different version of Hugo by changing the value of the `HUGO_VERSION` argument for the build. You *must* specify a version or the image will not build.
+Once the `kubernetes-hugo` image has been built locally, you can build the site:
+
+```bash
+$ make docker-serve
+
+# The underlying command:
+$ docker run \
+  --rm \
+  --interactive \
+  --tty \
+  --volume $(PWD):/src \
+  kubernetes-hugo:latest \
+  hugo
+```
+
+As when building without using a Docker container, the results of the build will be published to the `public` directory (the default output directory for [Hugo](https://gohugo.io), the static site generator used to build this site).
+
 ## Thank you!
 
 Kubernetes thrives on community participation, and we really appreciate your
-contributions to our site and our documentation!
+contributions to our site and our documentation!