Add configuration example

README.md

@@ -1,4 +1,37 @@
 DIUN - Docker Image Update Notifier
 ===================================
 
-This role installs [Duin](https://crazymax.dev/diun/).
+This role installs [Duin](https://crazymax.dev/diun/). Configuration is done via your `host_vars` files:
+
+```YAML
+diun_watch:
+  config: |
+    workers: 10
+    schedule: "0 */6 * * *"
+    jitter: 30s
+    firstCheckNotif: false
+
+diun_notif:
+  - name: mail
+    config: |
+      host: localhost
+      port: 25
+      ssl: false
+      insecureSkipVerify: false
+      from: diun@example.org
+      to:
+        - admin@example.org
+
+diun_providers:
+  - name: docker
+    config: |
+      watchByDefault: true
+      watchStopped: true
+      endpoint: "unix:///run/docker.sock"
+  - name: file
+    config: |
+      filename: {{ diun_configuration_path }}/{{ diun_provider_image_file }}
+
+diun_provider_images:
+  - name: docker.io/discourse/base:release
+```