Improve low power mode (#859)

-add switch on HASS
-avoid issue when using ESPWifiManualSetup
-Correct issue on gateway discovery on first connect
-stop processing during discovery

main/ZsensorDS1820.ino

@@ -113,7 +113,7 @@ void pubOneWire_HADiscovery() {
                       jsonTempc,
                       "", "", "°C",
                       0, "", "", true, "",
-                      "", "", "", "");
+                      "", "", "", "", false);
     }
   }
 #  endif