Fixing headers for gateway modules (#1554)

* Fixing red squiggles in VSCode/PlatformIO

* Lint issues

main/config_ONOFF.h

@@ -29,6 +29,7 @@
 extern void setupONOFF();
 extern void MQTTtoONOFF(char* topicOri, char* datacallback);
 extern void MQTTtoONOFF(char* topicOri, JsonObject& RFdata);
+extern void stateONOFFMeasures();
 /*----------------------------USER PARAMETERS-----------------------------*/
 /*-------------DEFINE YOUR MQTT PARAMETERS BELOW----------------*/
 #define subjectMQTTtoONOFF    "/commands/MQTTtoONOFF"