Moved standard_set() from King and Knight classes to Piece class since both the class called an identical standard_set() method. Added self.displacement argument to the King and Knight classes' move_set() method
Moved standard_set() from King and Knight classes to Piece class since both the class called an identical standard_set() method. Added self.displacement argument to the King and Knight classes' move_set() method

yarabarla/py-chess