creating CardGame.Domain library and corresponding test project to separate out generic card game classes from blackjack classes
moving the blackjack hand scoring responsibility to the BlackJackHand class, since it has rules specific to BlackJack.  Made the Hand implement a more generic scoring system
refactoring BlackJackHand to remove magic numbers and clarify the scoring rules
adding card deck domain entity to the card game with unit tests for basic card deck functionality (still need to implement deck shuffling)