title: Meteor: send message to user at hot code push
body: <p>How can I let the user know when they are getting a hot code push?</p>
  
  <p>At the moment the screen will go blank during the push, and the user will feel it's rather weird.  I want to reassure them the app is updating.</p>
  
  <p>Is there a hook or something which I can use?</p>