Rook movement
King movement (no castling)
Bishop movement
Changed empty square to x instead of space
Added curses support
Added a blank piece
Fixed curses drawing
Can now quit by pressing q
Added numbers and letters for rows and columns
Changed knight's letter to 'n' so its not the same

The knight's letter was the same as the king's letter, so the knight was
changed to 'n' and 'N'