Use lua for special level files

Game is playable, and should compile on linux and Windows.
Assumes you have a lua 5.3 library available.

Removes level compiler and associated files.
Replaces special level des-files with lua scripts.
Exposes some NetHack internals to lua:
 - des-table with commands to create special levels
 - nh-table with NetHack core commands
 - nhc-table with some constants
 - u-table with some player-specific data (u-struct)
 - selection userdata

Adds some rudimentary tests.

Adds new extended command #wizloadlua to run a specific script,
and #wizloaddes to run a specific level-creation script.

nhlib.lua is loaded for every lua script.

Download and untar lua:
  mkdir lib
  cd lib
  curl -R -O http://www.lua.org/ftp/lua-5.3.5.tar.gz
  tar zxf lua-5.3.5.tar.gz

Then make nethack normally.

dat/medusa-1.lua

@@ -0,0 +1,121 @@
+-- NetHack 3.6	medusa.des	$NHDT-Date: 1432512783 2015/05/25 00:13:03 $  $NHDT-Branch: master $:$NHDT-Revision: 1.10 $
+--	Copyright (c) 1989 by Jean-Christophe Collet
+--	Copyright (c) 1990, 1991 by M. Stephenson
+-- NetHack may be freely redistributed.  See license for details.
+--
+--
+-- These are the Medusa's levels :
+--
+
+des.level_init({ style = "solidfill", fg = " " });
+
+des.level_flags("mazelevel", "noteleport")
+
+des.map([[
+}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+}}.}}}}}..}}}}}......}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}....}}}...}}}}}
+}...}}.....}}}}}....}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}...............}
+}....}}}}}}}}}}....}}}..}}}}}}}}}}}.......}}}}}}}}}}}}}}}}..}}.....}}}...}}
+}....}}}}}}}}.....}}}}..}}}}}}.................}}}}}}}}}}}.}}}}.....}}...}}
+}....}}}}}}}}}}}}.}}}}.}}}}}}.-----------------.}}}}}}}}}}}}}}}}}.........}
+}....}}}}}}}}}}}}}}}}}}.}}}...|...............S...}}}}}}}}}}}}}}}}}}}....}}
+}.....}.}}....}}}}}}}}}.}}....--------+--------....}}}}}}..}}}}}}}}}}}...}}
+}......}}}}..}}}}}}}}}}}}}........|.......|........}}}}}....}}}}}}}}}}}}}}}
+}.....}}}}}}}}}}}}}}}}}}}}........|.......|........}}}}}...}}}}}}}}}.}}}}}}
+}.....}}}}}}}}}}}}}}}}}}}}....--------+--------....}}}}}}.}.}}}}}}}}}}}}}}}
+}......}}}}}}}}}}}}}}}}}}}}...S...............|...}}}}}}}}}}}}}}}}}.}}}}}}}
+}.......}}}}}}}..}}}}}}}}}}}}.-----------------.}}}}}}}}}}}}}}}}}....}}}}}}
+}........}}.}}....}}}}}}}}}}}}.................}}}}}..}}}}}}}}}.......}}}}}
+}.......}}}}}}}......}}}}}}}}}}}}}}.......}}}}}}}}}.....}}}}}}...}}..}}}}}}
+}.....}}}}}}}}}}}.....}}}}}}}}}}}}}}}}}}}}}}.}}}}}}}..}}}}}}}}}}....}}}}}}}
+}}..}}}}}}}}}}}}}....}}}}}}}}}}}}}}}}}}}}}}...}}..}}}}}}}.}}.}}}}..}}}}}}}}
+}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+]]);
+-- Dungeon Description
+des.region(selection.area(00,00,74,19),"lit")
+des.region(selection.area(31,07,45,07),"unlit")
+-- (must maintain one room definition; `filled=0' forces its room to be kept)
+des.region({ region={35,09, 41,10}, lit = 0, type="ordinary", prefilled = 1 })
+des.region(selection.area(31,12,45,12),"unlit")
+-- Teleport: down to up stairs island, up to Medusa's island
+des.teleport_region({ region = {01,01,05,17}, dir="down" })
+des.teleport_region({ region = {26,04,50,15}, dir="up" })
+-- Stairs
+des.stair("up", 05,14)
+des.stair("down", 36,10)
+-- Doors
+des.door("closed",46,07)
+des.door("locked",38,08)
+des.door("locked",38,11)
+des.door("closed",30,12)
+-- Branch, not allowed inside Medusa's building.
+des.levregion({ region = {01,00,79,20}, exclude = {30,06,46,13}, type = "branch" })
+-- Non diggable walls
+des.non_diggable(selection.area(30,06,46,13))
+-- Objects
+des.object({ id = "statue", x=36,y=10, buc="uncursed",
+             montype="knight", historic=1, male = 1, name="Perseus",
+             contents = function()
+                if math.random(0,99) < 75 then
+                   des.object({ id = "shield of reflection", buc="cursed", spe=0 })
+                end
+                if math.random(0,99) < 25 then
+                   des.object({ id = "levitation boots", spe=0 })
+                end
+                if math.random(0,99) < 50 then
+                   des.object({ id = "scimitar", buc="blessed", spe=2 })
+                end
+                if math.random(0,99) < 50 then
+                   des.object("sack")
+                end
+             end
+});
+
+-- Specifying explicit contents forces them to be empty.
+des.object({ id = "statue", contents = 0 })
+des.object({ id = "statue", contents = 0 })
+des.object({ id = "statue", contents = 0 })
+des.object({ id = "statue", contents = 0 })
+des.object({ id = "statue", contents = 0 })
+des.object({ id = "statue", contents = 0 })
+des.object({ id = "statue", contents = 0 })
+des.object()
+des.object()
+des.object()
+des.object()
+des.object()
+des.object()
+des.object()
+des.object()
+-- Random traps
+des.trap()
+des.trap()
+des.trap()
+des.trap()
+des.trap()
+des.trap("board",38,07)
+des.trap("board",38,12)
+-- Random monsters
+des.monster({ id = "Medusa", x=36,y=10, asleep=1 })
+des.monster("giant eel",11,06)
+des.monster("giant eel",23,13)
+des.monster("giant eel",29,02)
+des.monster("jellyfish",02,02)
+des.monster("jellyfish",00,08)
+des.monster("jellyfish",04,18)
+des.monster("water troll",51,03)
+des.monster("water troll",64,11)
+des.monster({ class = 'S', x=38, y=07 })
+des.monster({ class = 'S', x=38, y=12 })
+des.monster()
+des.monster()
+des.monster()
+des.monster()
+des.monster()
+des.monster()
+des.monster()
+des.monster()
+des.monster()
+des.monster()