Rename DropRoleSignal to DroppedRoleSignal.
Introduce data processing methods in ConnectionParticipantRole.
Introduce ErrorSignal in  ConnectioParticipantRole.
Preliminary V() implementaton.
Send multicast message inlt if MulticastService was succesfully established and improve error handling a bit.
Fix displaying GtkInfoBar when message is pushed during startup.
Use detailed exceptions during error handling in Connection ParticipantRole.
Make ConnectionParticipantRole dropping itself on failures.