Mqtt discovery for ha (#323)

* MQTT discovery factoring

* add DHT discovery

* BME topic macro change

* add sensors to ha discovery

* correct a comment typo #327

* let the possibility at buildtime to don't publish service data

* reduce string usage

* change MQTT ONOFF actuator to ON OFF commands instead of true false

* add ZactuatorONOFF discovery

* add simple publishing for GPIO input

* Add RF switch and gateway discovery

Zgateway2G.ino

@@ -135,8 +135,7 @@ boolean _2GtoMQTT(){
 #ifdef jsonPublishing
   void MQTTto2G(char * topicOri, JsonObject& SMSdata) {
     
-    String topic = topicOri;
-    if (topic == subjectMQTTto2G) {
+   if (strcmp(topicOri,subjectMQTTto2G) == 0){
       const char * sms = SMSdata["message"];
       const char * phone = SMSdata["phone"];
       trc(F("MQTTto2G json data analysis"));