Initial commit. Add setting of opponents and change test for setting opponents from pending to active.
Fix wins_ball method. Fix spec for .wins_ball to passing.
Add String score for player with 2 points.
Add full score tracking for players in both tennis.rb and spec.
Create failing test for setting Advantage to one player or the other.
Add setting of Advantage to pass test.
Add failing test for setting Deuce
Create #deuce to pass spec.
Add failing test for winning.