002c: Critical fix: Bug added in 002b statue fix would cause levels to 
      occassionally be impossible to make.  Fixed.  Also, some general
      cleanup of the "will this statue block things" code.
 
      Critical fix: Now there's a high recursion depth limit when retrying
      to plan a level; this way, the program does not freeze in an
      infinite loop if it's impossible to find a plan that meets the
      requirements. 

      Critical fix: An assert when making small deathmatch maps sometimes
      failed.  Fixed; assert removed.

      Feature added: Heretic "full game" megawads now make E6M1-3, with
      E6M3 not having an exit (neither in single player nor deathmatch)

002b: Critical fix: Door statues are now less likely to make it impossible
      to finish a level w/o the "noclip" (OK, "kitty") cheat code.

      Critical fix: Being unable to find a door fab no longer causes
      ObHack to crash and burn (we just try with a different level)

002a: "single player" and "coop" maps now have deathmatch starts (hack:
      I just put them where keys, player starts, and goodies are placed)
      With Heretic, "single player" maps have coop starts (hack: I put them
      where the gauntlets and chaos device are placed at SmiteMaster level)

002:

Heretic fixes: At smitemaster difficulty, we start the player with the 
               gauntlets and chaos device to give them a fighting chance 
               to get the crossbow.

General fixes: Not being able to find path no longer crashes; all levels that
               lead to secret level now must have both a normal and secret
               exit; levels now must have at least 5 non-scenery cells

Random seeder tweaked to give completely different levels than ObHack 001
            

001:

Heretic fixes: Doors now always work; secret doors now work

General fixes: Levels are now smaller; validator added to planner.lua
               to make sure a tiny level has exits; it is now possible
               to have deathmatch levels with only one row/column of cells

Not being able to find a staircase now causes Oblige to remake the level
instead of crashing and burning.


