title: FB api for Unity3d. Select all friends
body: <p>I use FB api for selecting friends for my app with following code (<a href="https://developers.facebook.com/docs/unity/reference/current/FB.AppRequest" rel="nofollow noreferrer">doc</a>)  </p>
  
  <pre><code>FB.AppRequest(
          message,
          null,
          new List&lt;object&gt; (){ "app_users" },
          null,
          null,
          jsonData,
          null,
          RequestResult
      );
  </code></pre>
  
  <p>But in window with selecting friends is no button <code>Select All</code>. Can I add it to native window? Or I have to write my own window with selecting?</p>