All Whisper.events listeners are now defined and bound in background.js,
and we no longer need global methods for opening the inbox and
conversation views, as those are handled by AppView or internally by
InboxView.
// FREEBIE
Add buttons for switching between the linking flow and the standalone
registration flow. The button and standalone registration are only
availble in a development environment.
// FREEBIE
Introduce a top level view for navigating between the inbox and the
installer, enabling an in-window relink flow. Navigation is driven
through the openInbox and openInstaller global events.
// FREEBIE