Beginnings of pathfinding functions.  Untested.
Added debug output for the pathfinder.

Fixed subtle errors in determining which adjacent regions are walkable.
Made the lambda in getRegionPath actually do what the comments say.
Created generic pathfinding class.
Open paths in every region.

For each region, every walkable hex must be reachable from every other
walkable hex.
Extend obstacles to overflow hexes.