title: Passing arguments to service in docker-compose.yml
body: <p>What I want to do is this:</p>
  
  <pre><code>version: '2'
  services:
    app:
      volumes:
        - .:/app
      image: redis-test
      entrypoint: /app/src/main.rb
      working_dir: /app
      links:
        - redis
    redis:
      image: redis
      args:
        - appendonly=yes
  </code></pre>
  
  <p>When I run <code>docker-compose up</code> it complains:</p>
  
  <blockquote>
    <p>Unsupported config option for services.redis: 'args'</p>
  </blockquote>
  
  <p>Is this possible?</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>More context: <a href="http://redis.io/topics/persistence#append-only-file" rel="nofollow">http://redis.io/topics/persistence#append-only-file</a></p>