Add config template plugin examples (#7)

plugins/kasane/README.md

@@ -0,0 +1,29 @@
+# Kasane
+
+[Kasane](https://github.com/google/kasane) is a layering tool for Kubernetes which utilises Jsonnet for deep object modification and patching.
+
+Use following steps to try the application:
+
+* Follow instructions from [custom_tools.md](https://github.com/argoproj/argo-cd/blob/master/docs/custom_tools.md) to make sure `kasane` binary is available in `argocd-repo-server` pod.
+* Register `kasane` plugin `argocd-cm` ConfigMap:
+
+```yaml
+apiVersion: v1
+data:
+  configManagementPlugins: |
+    - name: kasane
+      init:
+        command: [kasane, update]
+      generate:
+        command: [kasane, show]
+```
+* Create application using `kasane` as a config management plugin name.
+
+```
+argocd app create kasane \
+    --config-management-plugin kasane \
+    --repo https://github.com/argoproj/argocd-example-apps \
+    --path plugins/kasane \
+    --dest-server https://kubernetes.default.svc \
+    --dest-namespace default
+```