Keep alive packets are correctly filtered

recv_tcp_data now checks for keep alive packets directly after
reading the packet type.
Merge branch 'Network-Client-Dev' of https://github.com/DComm2013Network/CutThePower into stay_alive

Conflicts:
	src/Network/NetworkRouter.cpp
	src/Network/ServerCommunication.cpp
Added network clean up function, (hopefully) fixed client update system

The network clean up function will be called whenever there's an in
any of the network threads, and cleans up all variables shread between
the threads. The client update system now adds and deletes players
depending on what floor they're on.
Merge branch 'stay_alive' into Network-Client-Dev

Conflicts:
	src/Network/NetworkRouter.cpp