Generate heal location constants automatically, move data back to a single file.

data/maps/FourIsland/map.json

@@ -282,14 +282,5 @@
       "player_facing_dir": "BG_EVENT_PLAYER_FACING_ANY",
       "script": "FourIsland_EventScript_LoreleisHouseSign"
     }
-  ],
-  "heal_locations": [
-    {
-      "id": "HEAL_LOCATION_FOUR_ISLAND",
-      "x": 18,
-      "y": 21,
-      "respawn_map": "MAP_FOUR_ISLAND_POKEMON_CENTER_1F",
-      "respawn_npc": "LOCALID_FOUR_ISLAND_NURSE"
-    }
   ]
 }