title: How to get the current_user in a model observer?
body: <p>Given the following models:</p>
  
  <pre><code>Room (id, title)
  RoomMembers (id, room_id)
  RoomFeed, also an observer
  </code></pre>
  
  <p>When a Room title is updated, I want to create a RoomFeed item, showing who the user is who made the update.</p>
  
  <pre><code>@room.update_attributes(:title =&gt; "This is my new title")
  </code></pre>
  
  <p>Problem is in my observer for RoomFeed:</p>
  
  <pre><code>def after_update(record)
     # record is the Room object
  end
  </code></pre>
  
  <p>The is no way for me to get the user.id of the person who just made the update. How do I go about doing that? is there a better way to do the update so I get the current_user?</p>