Add Service and MqttSubscriber classes

- Create utils dir and move utils.py there

motor_passo/utils/utils.py

@@ -0,0 +1,12 @@
+import signal
+
+
+def _cleanup(*args, **kwargs):
+    import sys
+    import RPi.GPIO as gpio
+    gpio.cleanup()
+    sys.exit(0)
+
+
+def setup_cleanup():
+    signal.signal(signal.SIGINT, _cleanup)