expose shutoff

la_interface.h

@@ -1656,6 +1656,7 @@ void laSaveUserPreferences();
 void laEnsureUserPreferences();
 
 int laGetReady();
+void laShutoff();
 void laSetFrameCallbacks(laPreFrameF PreFrame, laPreDrawF PreDraw, laPostFrameF PostFrame);
 void laSetCleanupCallback(laCleanupF Cleanup);
 laWindow *laDesignWindow(int X, int Y, int W, int H);