1) Allow imports from the stock SMS database at any time.
2) Provide plaintext export support, in a format compatible with
the "SMS Backup And Restore" app.
3) Fix the DB weirdness on encrypted restore that previously
required killing the app.
1) Update the create, prompt, and change passphrase activities.
They are no longer dialog themed, and should look a little
less ugly.
2) Update the import DB activity to be less ugly and more robust.
3) Abstract all of the state handling stuff out of
ConversationListActivity. This is now handled by RoutingActivity,
which all launch intents move through.
