More interesting Gehennom levels

Instead of just plain old boring mazes, spice up Gehennom by
occasionally adding lava, iron bars, or even mines-style levels
(with lava, of course).

Of the fixed Gehennom levels, only Asmodeus' lair has been changed
to add some random lava pools.

Also some lua fixes and changes:
- Fixed a selection negation bounding box being wrong.
- Fixed a selection negated and ORed returning wrong results.
- des.map now returns a selection of the map grids it touched.
- When using des.map contents-function the commands following the
  map are not relative to it.

src/sp_lev.c

@@ -4600,12 +4600,12 @@ struct selectionvar *
 selection_not(struct selectionvar* s)
 {
     int x, y;
-
+    NhRect tmprect;
 
     for (x = 0; x < s->wid; x++)
         for (y = 0; y < s->hei; y++)
             selection_setpoint(x, y, s, selection_getpoint(x, y, s) ? 0 : 1);
-
+    selection_getbounds(s, &tmprect);
     return s;
 }
 
@@ -6466,6 +6466,7 @@ DISABLE_WARNING_UNREACHABLE_CODE
 /* map({ halign = "center", valign = "center", map = [[...]] }); */
 /* map({ map = [[...]], contents = function(map) ... end }); */
 /* map([[...]]) */
+/* local selection = map( ... ); */
 int
 lspo_map(lua_State *L)
 {
@@ -6493,6 +6494,7 @@ TODO: gc.coder->croom needs to be updated
     boolean has_contents = FALSE;
     int tryct = 0;
     int ox, oy;
+    struct selectionvar *sel;
 
     create_des_coder();
 
@@ -6527,6 +6529,7 @@ TODO: gc.coder->croom needs to be updated
         return 0;
     }
 
+    sel = selection_new();
     ox = x;
     oy = y;
  redo_maploc:
@@ -6575,6 +6578,7 @@ TODO: gc.coder->croom needs to be updated
         } else {
             mapfrag_free(&mf);
             nhl_error(L, "Map requires either x,y or halign,valign params");
+            selection_free(sel, TRUE);
             return 0;
         }
     } else {
@@ -6671,6 +6675,7 @@ TODO: gc.coder->croom needs to be updated
                 }
                 if (mptyp >= MAX_TYPE)
                     continue;
+                selection_setpoint(x, y, sel, 1);
                 levl[x][y].typ = mptyp;
                 levl[x][y].lit = FALSE;
                 /* clear out levl: load_common_data may set them */
@@ -6712,9 +6717,14 @@ TODO: gc.coder->croom needs to be updated
         if (nhl_pcall(L, 1, 0)){
             impossible("Lua error: %s", lua_tostring(L, -1));
         }
+        reset_xystart_size();
     }
 
-    return 0;
+    /* return selection where map locations were put */
+    l_selection_push_copy(L, sel);
+    selection_free(sel, TRUE);
+
+    return 1;
 }
 
 RESTORE_WARNING_UNREACHABLE_CODE