Removed async_continious_receive, as concept is not good/hard to impl.
Tried to stabilize UDPSocket API.
Migrated from ip/port to asio udp::endpoint.
Dropped MessageSocket.
Remover net:: prefix
Created NetDBSingleton for accessing NetDB.
Updated project settings.
Updated MessageDispatcher
Created MessageHandler interface and inherited CryptoHandler from it.
Created script for invoking protoc.
Rewritten UDPSocket_test for work with new API.