add nginx.conf

dockercompose/docker-compose.yml

@@ -1,10 +1,10 @@
 services:
   nginx:
-    image: nginx:latest
+    build:
+      context: ..
+      dockerfile: dockerfiles/nginx/Dockerfile
     ports:
       - "80:80"
-    volumes:
-      - ./nginx.conf:/etc/nginx/nginx.conf:ro
     depends_on:
       - db
       - etherpad