add actuator

Possibility to command a pin HIGH/LOW by MQTT #192

ZgatewayRF2.ino

@@ -212,7 +212,4 @@ void MQTTtoRF2(char * topicOri, char * datacallback) {
   }
 }
 
-bool to_bool(String const& s) { // thanks Chris Jester-Young from stackoverflow
-     return s != "0";
-}
 #endif