Merge pull request #12 from TisButMe/add_tromp_taylor_rules

Add tromp taylor rules
Fixed master to follow the changes in rustc
Merge pull request #15 from TisButMe/master

Fixed master to follow the changes in rustc
Added a Game abstraction which should make the use of the engine easier
Extracted get() from Board, to Game
Adds the Game module, with a get() and a with_Tromp_Taylor_rules methods
Moved the Ruleset definitions to Game
Moved all the show code to Game, and improved show slightly to display coords on the top & right of the board as well
moved the storage of the komi out of the board, to Game, and fixed related tests