0.6.3

• Added methods:
  • XY<usize>::saturating_sub()
  • XY<usize>::checked_sub()
  • XY<usize>::signed(self) -> XY<isize>
  • XY<O: Ord>::fits as a reverse of XY<O: Ord>::fits_in.
• Fixes some unchecked subtraction (they could cause panics in some cases).
  • Fixed #148 .