added rake task for testing
added mapping SCORE_IN_WORDS
introduced Player struct and updated say_score to use it
removed unused instance variables
added state interfaces/protocols
implemented states and updated TennisGame to use them
refactored RallyState
removed unneccessary bang from transition methods
added base state class
renamed state's transition method to won_point
delegated TennisGame won_point to state
added constant for tennis scores
Merge branch 'state-pattern'
broke up advantage and Win clauses
made variable names consistent
refactored say_score
renamed variables
updated TennisGame api for printing
added ScoreSayerVisitor. moved say_score logic to visitor.
refactored visitor's say_score method