Add is_uninitialized() and copying assigment operator to Identity.
Add Participant::set_identity() and simplify ParticipantCore constructor.
Make MainWindow responsible for creating ParticipantRow instances.
Fix issues in MainWindow::ParticipantRow.
Implement Participant::compare() for Identity class and hide ParticipantCore constructor.
Make ParticipantCores responsible for creating ParticipantCore instances.
Improve MainWindow::ParticipantRow, add update() method and fix moving constructor.
Implement constant version of Participant::get_multicast_participant_role().
Extend error codes in ParticipantCores.