Solved the mystery of subviews not showing up. Now the placeholder view is transparent and its subviews (the cards) are drawn on it.
Added tapGestureRecognizer, so that the cards can be chosen and the game is functional in that sense. The matched cards are being removed from the view, but other cards remain in their positions, this is next thing to do.

NEXT
- rearrange remaining cards after removal cards upon successful match
- import images for cards backs and face cards
- animate changes
- implement Set game
- go to the beach
- check in  before implementing cards repositioning on the board after successful match
scale card in its grid cell
added more comments and logs
1. Completed the repositioning and rearrangement of cards after the match
2. Completed Animations
3. Autolayout constraints done for Playing card and Set game (Set is not tested)
4. Deal button - reseals ok in any orientation and in any game state. Need to add animations for redial.

NEXT:
1. Setup KVO to notify VC when the game is finished. Take care of game over - when there is no match with remaining cards
2. Restore score label
3. Research the float stuff and how to compare the frames.
updated readme