Board & Pieces 0.5

• Add symbols for all Unicode chess-related codepoints.

• Change the signature of the board function.

  • Rename argument highlighted-squares to marked-squares.
  • Remove arguments highlighted-white-square-fill and highlighted-black-square-fill.
  • Add argument marking-color, together with marked-white-square-background and marked-black-square-background.
  • Support passing a length as arrow-stroke.

• Fix arrows not being displayed properly on reversed boards.