[Ultica] Changed fd_fire_int3 (#1159)

* Changed fd_fire_int3

added some free fire images distributed under CC0 license.

* Create credits.txt.txt

gfx/UltimateCataclysm/pngs_tall_32x64/fields/fd_fire_int3/credits.txt.txt

@@ -0,0 +1,2 @@
+some assets taken from:
+https://opengameart.org/content/fire-fx-burning-fire-animation

gfx/UltimateCataclysm/pngs_tall_32x64/fields/fd_fire_int3/fd_fire_int3.json

@@ -2,9 +2,13 @@
   "id": "fd_fire_int3",
   "animated": true,
     "fg": [
-      { "weight": 8, "sprite": "fd_fire_int3_0" },
       { "weight": 8, "sprite": "fd_fire_int3_1" },
       { "weight": 8, "sprite": "fd_fire_int3_2" },
-      { "weight": 8, "sprite": "fd_fire_int3_3" }
+      { "weight": 8, "sprite": "fd_fire_int3_3" },
+      { "weight": 8, "sprite": "fd_fire_int3_4" },
+      { "weight": 8, "sprite": "fd_fire_int3_5" },
+      { "weight": 8, "sprite": "fd_fire_int3_6" },
+      { "weight": 8, "sprite": "fd_fire_int3_7" },
+      { "weight": 8, "sprite": "fd_fire_int3_8" }
     ]
 }