Fix the reconnection sequence of EV3 color sensor after calibration

I have missed that the sensor enters the "STATE_CALIBRATE_DONE" state
after the calibration. From the reverse-engineered sources it seems to me
that in this mode, the sensor will no longer process CMD-SELECT messages.

This commit should fix this by cutting off NACKs to the sensor and
letting it reboot.

lib/ev3/color.py

@@ -223,5 +223,8 @@ class ColorSensor(EV3UartSensor):
         while items[0] == 0:
             items = self.read_raw_mode(ColorSensor.MODE_COL_CAL)
 
-        # switch the sensor back to a mode where it will not time out
+        # restart the sensor (after the calibration it will be stuck in the COL-CAL mode)
+        self.start_reset()
+
+        # wait for reconnect
         self.reflection()