add consolenotifier for peripheral system alerts

pi/roverd/gpio_toggle_dummy.go

@@ -28,3 +28,7 @@ func (g *GPIOToggle) On() bool {
 func (g *GPIOToggle) Configuration() GPIOToggleConfig {
 	return GPIOToggleConfig{}
 }
+
+func (g *GPIOToggle) BackendDescription() string {
+	return "native GPIO"
+}