1) Switch to new TextSecureAddress addressing, rather than mixing
long-based recipient IDs into libtextsecure.
2) Get rid of RecipientFormattingException throws in calls to
RecipientFactory.
Closes#2570
1) Migrate from GSON to Jackson everywhere.
2) Add support for storing identity key conflicts on message rows.
3) Add limited support for surfacing identity key conflicts in UI.
1) When registering with server, indicate that the server should
store messages and send notifications.
2) Process notification GCM messages, and connect to the server
to retrieve actual message content.
