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/Route22.asm

@@ -143,9 +143,11 @@ Route22Script1:
 
 StarterMons_50faf:
 ; starter the rival picked, rival trainer number
-	db STARTER2, 4
-	db STARTER3, 5
 	db STARTER1, 6
+	db STARTER2, 7
+	db STARTER3, 8
+	db STARTER4, 9
+	db STARTER5, 10
 
 Route22Script2:
 	ld a, [wIsInBattle]
@@ -300,9 +302,11 @@ Route22Script4:
 	ret
 
 StarterMons_510d9:
-	db STARTER2, 10
-	db STARTER3, 11
-	db STARTER1, 12
+	db STARTER2, 16
+	db STARTER3, 17
+	db STARTER1, 18
+	db STARTER4, 19
+	db STARTER5, 20
 
 Route22Script5:
 	ld a, [wIsInBattle]