Add HardwareRfid class implementation and integrate with main loop

lib/hardware/hardware_rfid.hpp

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <MFRC522.h>
+#include <functional>
+#include "hardware.pb.h"
+
+typedef std::function<void(const hardware_SensorToControlMessage&)> RfidCallback;
+
+class HardwareRfid {
+public:
+    HardwareRfid(uint8_t ssPin, uint8_t rstPin);
+    void begin();
+    void end();
+    void update();
+    void setCallback(RfidCallback cb);
+
+private:
+    MFRC522 _mfrc;
+    RfidCallback _callback;
+};