Issue generated from Tuleap's migration script. Originally submitted by: Stefan Monnier (monnier)

Make it possible for the user to send messages when the destination is not connected (and for the destination to receive the message when the sender is not connected any more either).

This kind of functionality is often absent from IM applications focused on "chatting", but it's indispensable if Ring wants to be a replacement for the likes of SMS and Whatsapp.