Fix object event graphic names (#731)

* Fixed object event graphic names

* Updated files and other variable names

* Fix from finding and replacing without matching case

* spritesheet updates

* Update flag name

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Co-authored-by: Marcus Huderle <huderlem@gmail.com>

data/maps/IndigoPlateau_PokemonCenter_1F/map.json

@@ -75,7 +75,7 @@
     },
     {
       "type": "object",
-      "graphics_id": "OBJ_EVENT_GFX_BLACKBELT",
+      "graphics_id": "OBJ_EVENT_GFX_BLACK_BELT",
       "x": 23,
       "y": 13,
       "elevation": 3,