title: Facebook Friend Selector for sending personalized message to ONE friend
body: <p>I need to implement a folw like that:
  - the user choose a friend in facebook
  - the user cannot chose more than one friend.
  - the app send a personalized message to the friend
  Testing with the         FB.ui({method: 'apprequests', etc...
  I see that is not possible to limit the number of friends to select and so I can't send a very personalized message.
  I think the only thing is to implement an 'in app' friend selector on my own... but looking for a simpler solution.</p>
  
  <p>thanks,
  A.</p>