We have to make some changes, and it's gotten to the point where
maintaining it as a separate library is more hassle than it's worth,
especially with Google releasing WorkManager as the preferred job
scheduling library.
Eliminate the concept of 'Recipients' (plural). There is now just
a 'Recipient', which contains an Address that is either an individual
or a group ID.
MMS groups now exist as part of the group database, just like push
groups.
// FREEBIE
If the contact doesn't have an image, render a color-coded
background and the first letter of the contact's name.
1) Don't display anything during recipient resolution.
2) Display a # icon in material gray for recipients with no name.
3) Display a material group icon in material gray for groups with
no avatar icon set.
Closes#3104
// FREEBIE
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) 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.
