Hass discovery improvments (#512)

Rename set commands to config
correct json buffer size and gateway name
replace state to cmd
replace set by config
add restart and erase command
add unicity to gateway command switches
BLE devices shouldn't be child of the gateway
make the BTtoMQTT topic consistent with other definitions

main/ZactuatorONOFF.ino

@@ -36,7 +36,7 @@ void MQTTtoONOFF(char *topicOri, JsonObject &ONOFFdata)
   if (cmpToMainTopic(topicOri, subjectMQTTtoONOFF))
   {
     trc(F("MQTTtoONOFF json data analysis"));
-    int boolSWITCHTYPE = ONOFFdata["state"] | 99;
+    int boolSWITCHTYPE = ONOFFdata["cmd"] | 99;
     int pin = ONOFFdata["pin"] | ACTUATOR_ONOFF_PIN;
     if (boolSWITCHTYPE != 99)
     {