Gym Leader Rematches!

This commit adds a large fundamental change to KEP, that being Gym Rematches.

This is achieved alongside a rework to the script that makes those post-game-gating NPCs shift around. If you add a new one, just add its constant to the lists you'll see in the Hall of Fame script.

It also fixes a few bugs:
- Fixed a bug where Cinnabar Gym loaded a fleet of Blaines. This occurred due to the way he is coded at base, and a misunderstanding I had when implementing his scaling. This is now fixed by standardising his gym script instead, while letting the gym trainers still use the old one.
- Fixed a bug where the Up-Grade NPC would not appear after beating Silph Co. 11F. However, Giovanni currently seems to have trouble with his text. This floor needs some re-coding anyway, given we need to add Jessie and James to it.

And some misc. changes:
- Changed the first Moon Stone in Mt. Moon to a Poison Stone for the Nidoking speedrunners
- Debug Mode now has a line of code to set up the post-game easily
- Changed Surge's initial battle text to Yellow's
- Added Sabrina's more accurate LGPE initial battle text, referring to the spoon she bent by accident

data/maps/objects/MtMoon1F.asm

@@ -20,7 +20,7 @@ MtMoon1F_Object:
 	object_event  7, 22, SPRITE_YOUNGSTER, STAY, DOWN, 6, OPP_BUG_CATCHER, 7
 	object_event 30, 27, SPRITE_YOUNGSTER, STAY, RIGHT, 7, OPP_BUG_CATCHER, 8
 	object_event  2, 20, SPRITE_POKE_BALL, STAY, NONE, 8, POTION
-	object_event  2,  2, SPRITE_POKE_BALL, STAY, NONE, 9, MOON_STONE
+	object_event  2,  2, SPRITE_POKE_BALL, STAY, NONE, 9, POISON_STONE
 	object_event 35, 31, SPRITE_POKE_BALL, STAY, NONE, 10, RARE_CANDY
 	object_event 36, 23, SPRITE_POKE_BALL, STAY, NONE, 11, ESCAPE_ROPE
 	object_event 20, 33, SPRITE_POKE_BALL, STAY, NONE, 12, POTION