Finished Required Task 2, added 4 more cards to the game.
Finished Required Task 3, added a text label to show the results of the last flip.  Also laid some of the groundwork for the extra credit by storing the entire flip history in an NSMutableArray in my model.
Finished Required Task 4, added a "Deal" button to start a new game and reset appropriate UI elements.
Added the UISegmentedControl for Required Task 5 to the Storyboard as well as some code to change the height. I also made some layout changes to make it look nice. It is not hooked up to anything yet.
Added ability for PlayingCard to match using 3 cards and award points appropriately based on difficulty of match. This is some of the groundwork for Required Task 5.
Fixed an issue where I wasn't taking every possible case into account when matching 3 cards and 2 have the same suit while 2 have the same rank. Should properly handle all cases for matching 3 cards now.
Finished Required Task 5, added the ability for the game mode to be switched to require 3 cards in a match and award/penalize points accordingly.
Finished Required Task 6, the game play mode control will now be disabled as soon as flipping starts and re-enabled when a new deal is initiated. I also removed the sender as an argument from the Deal button since it is not required.
Shortened the height of the cards to allow room for the extra credit slider control.
Finished Required Task 7, changed the card backs to be an image of my ZLogo card backs rather than the Apple logo and set them to appear and disappear correctly depending on the state of the individual card button.
Added UISlider to the interface in preparation for the extra credit. This required a little bit of rearranging and resizing as well.
Finished Extra Credit by adding slider that will allow you to look through the history of flips. It is hidden until there has been at least 2 flips. The flip history text is slightly transparent to indicate that it is not the most recent flip. Performing a new flip will automatically move the slider to the most current flip.
Moved flip history mechanism from my model into my view controller. I feel that it is more appropriately tracked in that location.
Added comments to CardMatchingGame implementation file (my controller) as well as fixed an issue where blank strings were being stored in my flipHistory. This bug was directly related to moving my flipHistory out of my model and into my controller.