Update INetworkSystem and some other related things.

public/engine/igameeventsystem.h

@@ -8,6 +8,7 @@
 #include <eiface.h>
 
 #include <tier1/utldelegate.h>
+#include <inetchannel.h>
 
 class IRecipientFilter;
 class CUtlSlot;
@@ -18,10 +19,6 @@ namespace google {
 	}
 }
 
-enum NetChannelBufType_t
-{
-};
-
 struct GameEventHandle_t__
 {
 	void *m_pUnknown;