- Initial picking stage of game. GH-5

- Player now derives Eq
- Game now has an "InProgress" type
- flop helper function to switch players back and forth.
- Starting deck now returns an empty list, instead of a list with the empty list in it.
- pick function transfers an unpicked pile to one of the players.

Signed-off-by: Damian "Pi" Lanningham <qrebound@gmail.com>
Merge pull request #5 from Quantumplation/GH-5

Picking stage