Added Update() and improved Close()

-Update will now attempt to accept a TCP Connection.
-StartServer() will run Update() once, instead of looping until
connection is established
-Close will now close the connection properly, and free the sockets
Added SetISServer() and Update()

-SetIsServer sets or re-sets wheter the client is server or client
-Upadte() calls Update() on the game client ( not main server )
-Cleanted up NetManager.cpp and added functions that were defined in
header file.
Rename method and changed function name in MenuManager

-Changed name of function that checks whether Lobby state has change to
HasLobbyStateChange()
-Added output in SetGameState to print old and new game state.
Imprved Lobby/multiplayer functionality

-Single player does not start any network features.
-Clicking Multiplayer and new game starts a new multiplayer game
	-"Waiting for second player" will be displayed until someone
	joins, and it's not possible to launch balls.
	-When starting a second client and selecting Multiplayer and
	Update ( temporary ), you will join the game of the other
	player. At this point, everything will be updated between the
	clients.
-Closing the game by pressing esc will close the game on both clients.
-Reselecting Multiplayer and New Game / Update will work properly as
above.

This needs to be tested, and the code needs to be cleaned up or changes
as it's quite messy at the moment.