public ActorMessageEnvelope <T> ConvertTo <T>()
        {
            var envelope = new ActorMessageEnvelope <T>();

            envelope.CopyFrom(this);
            return(envelope);
        }
        public static ActorMessageEnvelope NewFrom <T>(ActorMessageEnvelope <T> source)
        {
            var envelope = new ActorMessageEnvelope();

            envelope.CopyFrom(source);
            return(envelope);
        }
        public ActorMessageEnvelope ConvertToNonGeneric()
        {
            var envelope = new ActorMessageEnvelope();

            envelope.CopyFrom(this);
            return(envelope);
        }