Add docker-compose.yml with volume mount for db.json

Author: Raffael Herrmann

docker-compose.yml

@@ -0,0 +1,10 @@
+version: '3.8'
+
+services:
+  masscode-web:
+    build: .
+    ports:
+      - "8080:80"
+    volumes:
+      - ./db.json:/usr/share/nginx/html/data/db.json:ro
+    restart: unless-stopped