Add store protocol to the data obtained in DBUS GetUnreadMessages New libmodest-dbus-client version is 3.2.4.
Fixes NB#143352, add a DBus API to request inmmediate Send&Receive (like manual send&receive)
Converted libmodest-dbus-client into a new library package. Modest will depend on it (fix 1/2 for NB#132625).