ServerSocial: add simplified logging, refactor variables, add new functionality...

ServerSocial: add simplified logging, refactor variables, add new functionality...

 * simplified logging
 * replace console messages with logging
 * refactor variables
 * introduce setMemberOnlineState() to encapsulate all state-change functionality
 * introduce unicastMemberPresence() to notify over TCP streams
 * remove notifyMemberPresence(), memberOnline(), memberOffline()
 * set member offline when client disappears
 * at login use setMemberOnlineState() to do all required actions
 * add ServiceAddressMap updates from Neigbour multicast announcements (no longer done by NetworkServer*)
 * switch to logging via PacketHandler when LogServer is discovered
 * replace main() with generic app handling used in all other project executables