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-4.lua

@@ -0,0 +1,129 @@
+-- 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.
+--
+des.level_init({ style = "solidfill", fg = " " });
+des.level_flags("noteleport", "mazelevel")
+--
+-- Here the Medusa rules some slithery monsters from her 'palace', with
+-- a yellow dragon nesting in the backyard.
+--
+des.map([[
+}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+}}}}}}}}}}}}}}........}}}}}}}}}}}}}}}}}}}}}}}..}}}.....}}}}}}}}}}}----|}}}}}
+}}}}}}..----------F-.....}}}}}}}}}}}}}}}}..---...}}}}....T.}}}}}}}....|}}}}}
+}}}.....|...F......S}}}}....}}}}}}}...}}.....|}}.}}}}}}}......}}}}|......}}}
+}}}.....+...|..{...|}}}}}}}}}}}}.....}}}}|...|}}}}}}}}}}}.}}}}}}}}----.}}}}}
+}}......|...|......|}}}}}}}}}......}}}}}}|.......}}}}}}}}}}}}}..}}}}}...}}}}
+}}|-+--F|-+--....|F|-|}}}}}....}}}....}}}-----}}.....}}}}}}}......}}}}.}}}}}
+}}|...}}|...|....|}}}|}}}}}}}..}}}}}}}}}}}}}}}}}}}}....}}}}}}}}....T.}}}}}}}
+}}|...}}F...+....F}}}}}}}..}}}}}}}}}}}}}}...}}}}}}}}}}}}}}}}}}}}}}....}}..}}
+}}|...}}|...|....|}}}|}....}}}}}}....}}}...}}}}}...}}}}}}}}}}}}}}}}}.....}}}
+}}--+--F|-+--....-F|-|....}}}}}}}}}}.T...}}}}....---}}}}}}}}}}}}}}}}}}}}}}}}
+}}......|...|......|}}}}}.}}}}}}}}}....}}}}}}}.....|}}}}}}}}}.}}}}}}}}}}}}}}
+}}}}....+...|..{...|.}}}}}}}}}}}}}}}}}}}}}}}}}}.|..|}}}}}}}......}}}}...}}}}
+}}}}}}..|...F......|...}}}}}}}}}}..---}}}}}}}}}}--.-}}}}}....}}}}}}....}}}}}
+}}}}}}}}-----S----F|....}}}}}}}}}|...|}}}}}}}}}}}}...}}}}}}...}}}}}}..}}}}}}
+}}}}}}}}}..............T...}}}}}.|.......}}}}}}}}}}}}}}..}...}.}}}}....}}}}}
+}}}}}}}}}}....}}}}...}...}}}}}.......|.}}}}}}}}}}}}}}.......}}}}}}}}}...}}}}
+}}}}}}}}}}..}}}}}}}}}}.}}}}}}}}}}-..--.}}}}}}}}..}}}}}}..T...}}}..}}}}}}}}}}
+}}}}}}}}}...}}}}}}}}}}}}}}}}}}}}}}}...}}}}}}}....}}}}}}}.}}}..}}}...}}}}}}}}
+}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}.}}}}}}....}}}}}}}}}}}}}}}}}}}...}}}}}}
+}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
+]]);
+--
+local place = selection.new();
+place:set(04,08);
+place:set(10,04);
+place:set(10,08);
+place:set(10,12);
+--
+des.region(selection.area(00,00,74,19),"lit")
+des.region({ region={13,03, 18,13}, lit=1, type="ordinary", prefilled=1 })
+--
+des.teleport_region({ region = {64,01,74,17}, dir="down" });
+des.teleport_region({ region = {02,02,18,13}, dir="up" });
+--
+des.levregion({ region = {67,01,74,20}, type="stair-up" });
+local mx, my = place:rndcoord(1);
+des.stair("down", mx, my)
+--
+des.door("locked",04,06)
+des.door("locked",04,10)
+des.door("locked",08,04)
+des.door("locked",08,12)
+des.door("locked",10,06)
+des.door("locked",10,10)
+des.door("locked",12,08)
+--
+des.levregion({ region = {27,00,79,20}, type="branch" });
+--
+des.non_diggable(selection.area(01,01,22,14));
+--
+des.object("crystal ball", 07,08)
+--
+local px, py = place:rndcoord(1);
+des.object({ id="statue",x=px, y=py, 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
+});
+--
+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 })
+for i=1,8 do
+   des.object()
+end
+--
+for i=1,7 do
+   des.trap()
+end
+--
+des.monster("Medusa", mx, my)
+des.monster("kraken", 07,07)
+--
+-- the nesting dragon
+des.monster({ id = "yellow dragon", x=05, y=04, asleep=1 })
+if math.random(0,99) < 50 then
+   des.monster({ id = "baby yellow dragon", x=04,y=04, asleep=1 })
+end
+if math.random(0,99) < 25 then
+   des.monster({ id = "baby yellow dragon", x=04, y=05, asleep=1 })
+end
+des.object({ id = "egg", x=05, y=04, montype="yellow dragon" });
+if math.random(0,99) < 50 then
+   des.object({ id = "egg", x=05, y=04, montype="yellow dragon" });
+end
+if math.random(0,99) < 25 then
+   des.object({ id = "egg", x=05, y=04, montype="yellow dragon" });
+end
+--
+des.monster("giant eel")
+des.monster("giant eel")
+des.monster("jellyfish")
+des.monster("jellyfish")
+for i=1,14 do
+   des.monster("S")
+end
+for i=1,4 do
+   des.monster("black naga hatchling")
+   des.monster("black naga")
+end