Release 1.1.1 card slots, card attributes, expiration and visual fixes

• Added sub-slots to cards, as shown in the 'barn' card from Example B.
• Added helper functions for managing "card qualities", customizable attributes that an be checked and modified during gameplay.
• Added the "expires" feature, which will cause cards to disappear. Supported by the new helper functions.
• Fixed z-order visual glitches.