Pikachu/Eevee Mode

So some bits of this are untested, but the base starters are unaffected. I had to work a lot with the sprite limits so Oak's lab has been changed a bit.

This adds a Pikachu and Eevee "mode" to the game, allowing you to pick them as starters. When doing so, the Rival will always pick the opposite.

There are some glitches;
- Picking Charmander makes Blue erase himself from existence
- Picking from anywhere other than the front of the table may have odd results.
- Oak has to be shown in the lab at the start from now on for some reason; side effect of removing the dexes, there's definitely a fix for this.
These are from me not finishing the ball picking process - it was a little weird.

Parties based on starters have been updated but I had to cut out a lot of unused trainer slots.

Also the unused names were removed.

scripts/CeruleanCity.asm

@@ -143,17 +143,28 @@ CeruleanCityScript1:
 
 	; select which team to use during the encounter
 	ld a, [wRivalStarter]
-	cp STARTER2
+	cp STARTER1
 	jr nz, .NotSquirtle
-	ld a, $7
+	ld a, $11
 	jr .done
 .NotSquirtle
 	cp STARTER3
 	jr nz, .Charmander
-	ld a, $8
+	ld a, $12
 	jr .done
 .Charmander
-	ld a, $9
+	cp STARTER2 ; changes start here
+	ld a, $13
+	jr nz, .Pikachu
+	jr .done
+.Pikachu ;
+	cp STARTER4 
+	jr nz, .Eevee
+	ld a, $14
+	jr .done
+.Eevee
+	ld a, $15
+	jr .done
 .done
 	ld [wTrainerNo], a
 	ld a, 1