Added boolean for bonus move
Added a test for the bonus
Merge branch 'master' into Bonus
A bonus move is awarded when a player reaches 18 points in one color
Updated bonus rules
Merge branch 'master' into Bonus
Refactored the call to switchPlayer() out of Game.placeTile().
Added field playsLeft to player and getters and setters
All tests but one now pass
Playing reduces the number of plays left for the current player
Added bonus turn for reaching 18 in one color
Player gains bonus turns for hitting 18 points in a color (once per color).
Bonus scoring is incorporated into DrawBoard.