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

data/maps/VerdanturfTown/map.json

@@ -196,12 +196,5 @@
       "player_facing_dir": "BG_EVENT_PLAYER_FACING_ANY",
       "script": "VerdanturfTown_EventScript_RusturfTunnelSign"
     }
-  ],
-  "heal_locations": [
-    {
-      "id": "HEAL_LOCATION_VERDANTURF_TOWN",
-      "x": 16,
-      "y": 4
-    }
   ]
 }