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

scripts/SilphCo11F.asm

@@ -186,6 +186,7 @@ MissableObjectIDs_62194:
 	db HS_SAFFRON_CITY_B
 	db HS_SAFFRON_CITY_C
 	db HS_SAFFRON_CITY_D
+	db HS_SAFFRON_CITY_UP_GRADE
 	db -1 ; end
 
 MissableObjectIDs_6219b:
@@ -198,7 +199,6 @@ MissableObjectIDs_6219b:
 	db HS_SAFFRON_CITY_7
 	db HS_SAFFRON_CITY_E
 	db HS_SAFFRON_CITY_F
-	db HS_SAFFRON_CITY_UP_GRADE
 	db HS_SILPH_CO_3F_1
 	db HS_SILPH_CO_3F_2
 	db HS_SILPH_CO_4F_1