Display’s a non-dismissable copy of the beta/media message in the footer after dismissing the standard message

- messages broadcast a `’message:hidden:messageId` event when dismissed
- media & beta messages are shown in the footer once dismissed
- media & beta messages reordered slightly, to avoid unnecessary string concatenation 
If we want this logic on all release message and not just the global one, why don't you move the logic inside `message.js` instead of duplicating it everywhere making it more DRY.