Rearranged the packet and serial code to make more sense

This mostly just reimplements the best parts of the discarded branch:

> discard-encapsulated-packets

There may still be some work needed.

server/server_application.hpp

@@ -30,6 +30,7 @@
 
 //common utilities
 #include "udp_network_utility.hpp"
+#include "serial_packet.hpp"
 #include "config_utility.hpp"
 #include "singleton.hpp"