code: func setup(c *caddy.Controller) error {
  	mdconfigs, err := markdownParse(c)
  	if err != nil {
  		return err
  	}
  
  	cfg := httpserver.GetConfig(c)
  
  	md := Markdown{
  		Root:       cfg.Root,
  		FileSys:    http.Dir(cfg.Root),
  		Configs:    mdconfigs,
  		IndexFiles: []string{"index.md"},
  	}
  
  	cfg.AddMiddleware(func(next httpserver.Handler) httpserver.Handler {
  		md.Next = next
  		return md
  	})
  
  	return nil
  }
docs: // setup configures a new Markdown middleware instance.