Add docker-compose example to configuration (#129)

CONFIGURATION.md

@@ -8,6 +8,24 @@ docker run -e SONARR_API_KEY=YOUR_API_KEY -e RADARR_API_KEY=YOUR_API_KEY -e PLEX
 ```
 Note: If you are adding new environment variables or other configuration, add it before the `nylonee/watchlistarr` part
 
+### Docker-compose variant
+```
+version: '3.8'
+services:
+ watchlistarr:
+ image: nylonee/watchlistarr
+ environment:
+ SONARR_API_KEY: YOUR_API_KEY
+ RADARR_API_KEY: YOUR_API_KEY
+ PLEX_TOKEN: YOUR_PLEX_TOKEN
+ volumes:
+ - config:/app/config
+ restart: unless-stopped
+
+volumes:
+ config:
+```
+
 In most consoles, you are able to add a \ to denote a breakline, which makes this command easier to read and manipulate. For example:
 ```bash
 docker run \