better example

include/sp/default/DefaultPacketHandler.h

@@ -0,0 +1,9 @@
+#pragma once
+
+#include <sp/protocol/GenericHandler.h>
+
+// the tuple AllPackets must be defined !
+
+namespace sp {
+class PacketHandler : public sp::GenericHandler<PacketMessage, AllPackets> {};
+}  // namespace sp