Revert "* The default baudrate (230400) can't be used for Arduino UNO. Use 250000 instead"

This reverts commit 15b7b1eec1947f37fe42bb54b45f4d0a1c44d4ca.

Conflicts:
	IoTPy/pyuper/ioboard.py
* Reverted the changed made for Arduino.
  I've created a branch for Arduino, so these changes shouldn't be on
  upstream repo for now.