Add Kubernetes integration content

[changelog:added]

docs/integration/kubernetes.md

@@ -1 +1,37 @@
-Coming soon
+We provide a utility called [k8svent][] that sends events from your
+Kubernetes cluster(s) to Atomist so skills can take action.
+
+Here is a video walking you through setting up the Atomist Kubernetes
+integration.
+
+<div style="text-align:center;">
+  <iframe width="560" height="315" src="https://www.youtube-nocookie.com/embed/wuRDAi9mQmY" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
+</div>
+
+[k8svent]: https://github.com/atomist/k8svent (Atomist k8svent utility)
+
+## Connect to Kubernetes
+
+1.  From **Manage > Integrations**, choose the Kubernetes integration.
+2.  Enter a name for the Kubernetes cluster you want to add.
+    Typically this is something like "production" or "k8s-testing".
+3.  Click **Add**.
+4.  Copy the installation instructions from the popup.
+5.  Paste the installation command into a terminal and hit **Enter**.
+
+The installation command will use the [`kubectl`][kubectl] utility and
+your current Kubernetes configuration context to install the Atomist
+utility.  So make sure you have `kubectl` installed and configured to
+operate on the cluster you are adding.
+
+![Atomist Kubernetes Cluster Integration](img/kubernetes/kubernetes-integration.png)
+
+To add additional clusters, click **Add another Kubernetes cluster**
+and repeat steps 2–5.
+
+!!! error
+    If you get an error when trying to install the Atomist Kubernetes
+    integration, you may not have permissions to do so on your cluster.
+    Ask your Kubernetes cluster admin for help.
+
+[kubectl]: https://kubernetes.io/docs/reference/kubectl/overview/ (kubectl Overview)