title: Checking authentication with play2-auth
body: <p>In the code below, there's  a play2-auth authorization check. In the first method it checks that the authority required is <code>NormalUser</code> and in the second method <code>Administrator</code>.</p>
  
  <p>In my case, there may be even more roles (such as <code>Security Officer</code>) that are created by the user. Is it possible to have StackAction check against a user role that is dynamically created in the system?</p>
  
  <pre><code>  def detail(id: Int) = StackAction(AuthorityKey -&gt; NormalUser) { implicit request =&gt;
      val title = "messages detail "
      Ok(html.message.detail(title + id))
    }
  
    def write = StackAction(AuthorityKey -&gt; Administrator) { implicit request =&gt;
      val title = "write message"
      Ok(html.message.write(title))
    }
  </code></pre>