Beta-3 changes

- remove I2C init  from usermods
- PCF8574 (&co) port expander support
- refactor PIR &  Rotary encoder & 4LD
- reboot race condition
- optimisations

usermods/Si7021_MQTT_HA/usermod_si7021_mqtt_ha.h

@@ -13,14 +13,6 @@
 
 Adafruit_Si7021 si7021;
 
-#ifdef ARDUINO_ARCH_ESP32 //ESP32 boards
-uint8_t SCL_PIN = 22;
-uint8_t SDA_PIN = 21;
-#else //ESP8266 boards
-uint8_t SCL_PIN = 5;
-uint8_t SDA_PIN = 4;
-#endif
-
 class Si7021_MQTT_HA : public Usermod
 {
   private:
@@ -184,7 +176,6 @@ class Si7021_MQTT_HA : public Usermod
     {
       if (enabled) {
         Serial.println("Si7021_MQTT_HA: Starting!");
-        Wire.begin(SDA_PIN, SCL_PIN);
         Serial.println("Si7021_MQTT_HA: Initializing sensors.. ");
         _initializeSensor();
       }