Add and document an example production docker-compose.yml file.

docker/README.txt

@@ -4,6 +4,8 @@ This directory contains files necessary to build the farmOS Docker image, along
 with example `docker-compose.yml` files that can be used for running farmOS in
 Docker containers.
 
+## Development environment
+
 To run a farmOS development environment, copy `docker-compose.development.yml`
 into a new directory on your server, rename it to `docker-compose.yml` and run
 `docker-compose up`.
@@ -13,4 +15,11 @@ PostGIS, copy the `docker-compose.override.postgis.yml` file to the same
 directory and rename it to `docker-compose.override.yml`. This will override
 the `db` configuration from `docker-compose.development.yml`.
 
+## Production environment
+
+To run a farmOS production environment, use `docker-compose.production.yml` as
+an example for building your own configuration. Note that this example does not
+include a database. It is assumed that in production environments the database
+will be managed outside of Docker.
+
 For more information, see farmOS.org/hosting/docker.

docker/docker-compose.production.yml

@@ -0,0 +1,8 @@
+version: '2'
+services:
+  www:
+    image: farmos/farmos:7.x-1.1
+    volumes:
+      - './.data/www:/var/www/html'
+    ports:
+      - '80:80'