This is a block-falling game similar to Tetris. I started it because I'm curios how TDD applies to games.

Blocks falling in a slim well v0.1:
* The well is one block wide
* Blocks fall down from the top all the way to the bottom
* The game ends when the blocks stack over each other and reach the top

Movable blocks falling in a well v0.2:
* The well is 10 blocks wide
* Blocks fall down from the top to the bottom
* Player can move blocks left and right
* The game ends when the blocks stack over each other and reach the top

Lines disappear v0.3:
* Same as v0.2
* Whenever a line is formed, it disappears and gets counted

Real pieces v0.4:
* Replace the blocks with I pieces

Pieces can rotate v0.4:
* Add rotation

All pieces v0.5:
* Add J, L, O, S, T, Z