Also, a SystemFeedback model no longer has a `type`, it has an `intent`. This is
because SystemFeedback views have `type`, as well, and this prevents a naming
collision.
It appears that one notification stealing focus from another causes some weirdness:
both clicking on a button on one view triggers the event on both views (the original
and the new view that stole the div). As long as the first view does *not* define
any click events, everything is fine -- this is the case for the saving notification.
I'll worry about the reason for this later; it has something to do with views
listening to models even after they no longer should be.
