add additional logging information

launcher/launcher.cpp

@@ -767,6 +767,8 @@ bool CSourceAppSystemGroup::PreInit()
 {
 	if ( !CommandLine()->FindParm( "-nolog" ) )
 		DebugLogger()->Init("engine.log");
+	else
+		DebugLogger()->Disable();
 
 	CreateInterfaceFn factory = GetFactory();
 	ConnectTier1Libraries( &factory, 1 );