Removing unused levels.  Adding some more tests, but there's a funny one
at level 3 that eventually solves, but after a long time.  Currently
failing because of Solver limits.
Removing commented out code (missed it that last checkin)
Pulling out test 11 of the fullpuzzles.  Need a better Solver
Some refactoring to work with String puzzle a little more easily.  Using
X instead of " " in puzzle, because that make it easier to hand in as a
web param.  Changed tests to reflect (and test) this change.
Making it easier to deal with string input
Getting close.  Added new test that creates a "puzzle book" of different
levels.  Need to turn this into an HTML page.
Adding puzzle entry to create buttons better
Don't allow ambiguous puzzles