When doing this during startup it can be done by regular cleanup measures.
This also moves two larger chunks of networking code out of game.cpp.
Nevertheless, the fact that enet is a very dirty library which directly depends on Windows types is a big problem because it bleeds Windows definitions everywhere thanks to poor abstraction in all relevant layers.
Note: enet uses 'malloc' and 'free' as field names in a struct - this does not work with any compiler using some sort of heap instrumentation that #defines these names!
This had to be changed to allow MSVC debug builds to compile again.
