readme: Add the cell at coordinate (0, 0).
readme: Add the cell at coordinate (0, 1).
readme: Add the cell at coordinate (0, 2).
readme: Add the cell at coordinate (0, 3).
readme: Add the cell at coordinate (0, 4).
readme: Add the cell at coordinate (0, 5).
readme: Add the cell at coordinate (0, 6).
readme: Add the cell at coordinate (1, 3).
readme: Add the cell at coordinate (2, 3).
readme: Add the cell at coordinate (3, 0).
readme: Add the cell at coordinate (3, 1).
readme: Add the cell at coordinate (3, 2).
readme: Add the cell at coordinate (3, 3).
readme: Add the cell at coordinate (3, 4).
readme: Add the cell at coordinate (3, 5).
readme: Add the cell at coordinate (3, 6).
readme: Add the cell at coordinate (5, 0).
readme: Add the cell at coordinate (5, 1).
readme: Add the cell at coordinate (5, 2).
readme: Add the cell at coordinate (5, 3).