* Add ability to specify pulse length in ZactuatorONOFF
Add an additional parameter to the MQTT message to control the actuatorONOFF pulse length e.g. `mosquitto_pub -t home/OpenMQTTGateway_MEGA/commands/MQTTtoONOFF -m '{"gpio":15,"cmd":"high_pulse","pulse_length":25}'`
* Simplify initialization of pulselength