Refactored code to make CardGameViewController generic to work for different card decks. PlayingCardGameViewController has controller logic specific to PlayingCards.

Storyboard
  —  switched the view to refer to PlayingCardGameViewController
Fixed duplicate connections from some buttons to the outlet collection.
Added another CardGameController (and UI) to validate concept of shared of base CardGameViewController
Minor refactoring changes:
 - Improved naming for method -  match to weightedMatch
Basic version of Set Card Game included.
TODO: Refine UI.
Added a PlayingCardIcon image set and tried to use it for the UITabBarController but was not successful in loading the icons for the images.
Added support for displaying card content using attributed strings.
Enhanced reporting of (mis)matches using NSAttributed string - to better represent Set cards.
Eliminated references to no-longer used property - selectionImpactString. Was previously replaced by selectionImpactStringAttr
Added macro to reduce repetitive code for verifying object is of a certain type before casting to that type.
Used this macro to validate card is kind of type SetCard before performing SetCard specific operations.
Included ability to override content shown for card when not selected.
Added background image for the case where we want to show the card content when not chosen. This background image provides more clarity to the card content than the Stanford image.
A different background image is used when easy mode is enabled.
Added support for tracking (history) impact of selections
Added navigation view controllers. Hierarchy : TabController-->NavigationController-->CardGameViewController.
This is in preparation to show the history of selections and impact.
Note, the score and redeal button are hidden by the navigation header (TODO: Fix later)
Added View for displaying History and logic for transfer of data from game controller to history controller.
Data formatted with new line for each selection.
Text Area size and scrolling need to be fixed.
Text Area size and scroll issue fixed for iPhone 6
Added separator between representation of multiple cards - to avoid two cards appearing as one.
Adjusted layout of SetGame and CardGame views for iPhone 6 - All cards, score, redial and selection impact buttons nicely laid out
Minor change of arg type of  CardGameViewController::touchRedealButton:(UIButton *)sender to  :touchRedealButton:(id)sender to share the method with BarButtonItem action.
Extra Redeal button setup on the NavigationBar. Remove it in next check-in
Removed the previous Redeal button (Moved to navigation bar)
Removed unused Mode label.
Added a segmented control to control match mode.
Changed previous matchMode method to numberOfCardsToMatch