More changes.  This is degrading right now
Yea!  Now solves all puzzles.  So far, the best solver
Best solver so far.

Refactored tests, cleaned up the constructors
Things reasonably fixed up.

Cut the number of lookaheads to 3, which seems to produce reasonable
puzzles.  Hard to really generate a specific puzzle on demand.

I don't know what changed, but for some reason coverage=25 never seems
to produce a solvable puzzle.

Updated the fullpuzzle to include a week of puzzles from the Merc.
Dumping more statistics