Semi-operable nine-card template version

This version works pretty well with a hand of 12 or fewer cards, but it is ugly
and the sets are identified using a coordinate system that is not defined
anywhere for the user to see. The main things I would like to fix with this
version of the app the following:

 - Allow the user to change the number of cards in the hand (e.g. to 15 and
   back to 12).

 - Find a better way to point out a set. Maybe highlight the cards in the set.

 - Fix the layout so it looks nicer.