Fix for login window not disappearing

We need to wait to do other actions until after the modal
disappears.  Add a new event, `user:login:success`, which
most apps should bind to that is what happens after
the modal successfully disappears and the page is reloaded.

Don't bind to `user:login` or `user:logout` unless there's
a good reason, instead use
`user:login:success` and `user:logout:success`