test passes.
Refactor: moved tests into context
Refactor: renamed get_points and ball_win_for
Add test for game won by player 1
test passes
Refactor: extracted multiple_win_method
Add test for player 2 win
Add test for scoring after game is won
test passes
cleaned up scoreboard code
Add test for advantage after deuce
refactored point representation
Add test for win  with point after advantage, test passes
Add test for going back to deuce after other player point.
Corrected previous test.
test passes
cleaned up some code
Add test first test for tennis set, passes