feat: split out system() calls from the rest of MasterServer (#1368)

dMasterServer/Start.h

@@ -0,0 +1,6 @@
+#pragma once
+#include "dCommonVars.h"
+
+void StartAuthServer();
+void StartChatServer();
+void StartWorldServer(LWOMAPID mapID, uint16_t port, LWOINSTANCEID lastInstanceID, int maxPlayers, LWOCLONEID cloneID);