title: Reward when a friend accepts app invite
body: <p>In my facebook game I'm trying to create a system where a user can invite their friend to the game, I want it so that if they accept the invite then they both get rewarded I have read the API docs but not quite sure how to link who invited who.</p>
  
  <p>Any help appreciated</p>
  
  <p>Thanks,</p>
  
  <p>Jack.</p>