Implements Card and PlayingCard

spec folder for testing
Inheritance to make Card more extensible
Implements Card and PlayingCard

spec folder for testing
Inheritance to make Card more extensible
Merge branch 'OODesign' of https://github.com/ggw215/algorithm_practice into OODesign

Conflicts:
	OODesign/blackjack/card.rb
Implements a PlayingCardDeck

Initialized with the 52 card deck:
Generic playing card deck where Ace is high, 
colors are red and black with normal suits
Merge pull request #4 from ggw215/OODesign

Playing Card Deck