Add ability to inverse notify PIR LED (#765)

main/ZsensorHCSR501.ino

@@ -63,7 +63,7 @@ void MeasureHCSR501() {
       }
     }
 #  ifdef HCSR501_LED_NOTIFY_GPIO
-    digitalWrite(HCSR501_LED_NOTIFY_GPIO, pirState);
+    digitalWrite(HCSR501_LED_NOTIFY_GPIO, pirState == HCSR501_LED_ON);
 #  endif
     if (HCSR501data.size() > 0)
       pub(subjectHCSR501toMQTT, HCSR501data);

main/config_HCSR501.h

@@ -33,6 +33,10 @@ extern void HCSR501toMQTT();
 #define subjectHCSR501toMQTT "/HCSR501toMQTT"
 //#define HCSR501_LED_NOTIFY_GPIO 4 //Uncomment this line to mirror the state of the PIR sensor to the specified GPIO
 
+#if defined(HCSR501_LED_NOTIFY_GPIO) && !defined(HCSR501_LED_ON)
+#  define HCSR501_LED_ON HIGH
+#endif
+
 #ifndef TimeBeforeStartHCSR501
 #  define TimeBeforeStartHCSR501 60000 //define the time necessary for HC SR501 init
 #endif