Celeste Hill Gate & other things

- New Celeste Hill Gate location so the entrance into the location makes more sense. Also took the opportunity to include more lore. This replaces Pokemon Tower 4F.
- Fixed a bug that caused the Cat icon to not animate correctly.
- Made the infinite Nugget glitch work properly because I was stupid and didn't test it.
- Luxwan now uses the Small Bird icon to fit with the rest of the line.
- Nidoreign has a new Pokedex entry and classification, centred on the Nido's origins in the Moon Rabbit of Asian mythology.

data/maps/objects/CelesteHillGate.asm

@@ -0,0 +1,17 @@
+CelesteHillGate_Object:
+	db $a ; border block
+
+	def_warp_events
+	warp_event  4,  0, CELESTE_HILL_OUTSIDE, 1
+	warp_event  5,  0, CELESTE_HILL_OUTSIDE, 2
+	warp_event  4,  7, CITRINE_CITY, 5
+	warp_event  5,  7, CITRINE_CITY, 5
+
+	def_bg_events
+
+	def_object_events
+	object_event  8,  4, SPRITE_SCIENTIST, WALK, LEFT_RIGHT, 1 ; person
+	object_event  1,  4, SPRITE_YOUNGSTER, STAY, NONE, 2 ; person
+	object_event  1,  5, SPRITE_SMALL_BIRD, WALK, ANY_DIR, 3 ; person
+
+	def_warps_to CELESTE_HILL_GATE