title: SSL certificates or other files not showing in Docker file structure
body: <p>I have a Docker build for Gitlab, I created some ssl certificates and other files I need to pull in.  However when I exec into the container bash the files are not visible.</p>
  
  <pre><code>gitlab:
    image: 'gitlab/gitlab-ce:9.1.0-ce.0'
    restart: always
    hostname: 'gitlab.example.com'
    links:
      - postgresql:postgresql
      - redis:redis
    environment:
      GITLAB_OMNIBUS_CONFIG: |
        postgresql['enable'] = false
        gitlab_rails['db_username'] = "gitlab"
        gitlab_rails['db_password'] = "gitlab"
        gitlab_rails['db_host'] = "postgresql"
        gitlab_rails['db_port'] = "5432"
        gitlab_rails['db_database'] = "gitlabhq_production"
        gitlab_rails['db_adapter'] = 'postgresql'
        gitlab_rails['db_encoding'] = 'utf8'
        redis['enable'] = false
        gitlab_rails['redis_host'] = 'redis'
        gitlab_rails['redis_port'] = '6379'
        external_url 'https://gitlab.example.com:30080'
        nginx['ssl_certificate'] = '/etc/gitlab/trusted-certs/gitlab.example.com.crt'
        nginx['ssl_certificate_key'] = '/etc/gitlab/trusted-certs/gitlab.example.com.key'
    ports:
      - "30080:30080"
      - "30022:22"
  postgresql:
    restart: always
    image: postgres:9.6.2-alpine
    environment:
      - POSTGRES_USER=gitlab
      - POSTGRES_PASSWORD=gitlab
      - POSTGRES_DB=gitlabhq_production
  redis:
    restart: always
    image: redis:3.0.7-alpine
  </code></pre>