Bill's Garden, add Rowan NPC

Rowan NPC added to Cinnabar Lab, just a little cute thing.

Bill's Garden could see many revisions, what's here is the bare minimum. Here's what's done:
- Nidorino NPC blocks it off and is unlocked in the post-game. This currently contradicts the myth - I have a plan for this soon.
- Wild Pokemon are the "non-reproducibles" given in Stadium; starters and eevee are mandatory given those were common in the myth
- Hisui forms should be added when possible
- I had to remake Martha's map in the forest tileset so leaving would be possible
- Everything is at a point where it functions

data/wild/maps/BillsGarden.asm

@@ -0,0 +1,26 @@
+BillsGardenWildMons: ; wild mons are definitely edit-able
+	def_grass_wildmons 10 ; encounter rate
+	db 46, EEVEE
+	db 46, EEVEE
+	db 46, CHARMANDER
+	db 49, BULBASAUR
+	db 49, HITMONTOP
+	db 52, HITMONCHAN
+	db 49, HITMONLEE
+	db 52, KABUTO
+	db 53, OMANYTE
+	db 53, AERODACTYL
+	end_grass_wildmons
+
+	def_water_wildmons 10 ; encounter rate
+	db 40, SQUIRTLE
+	db 40, SQUIRTLE
+	db 40, SQUIRTLE
+	db 40, SQUIRTLE
+	db 40, SQUIRTLE
+	db 40, SQUIRTLE
+	db 40, SQUIRTLE
+	db 40, BLASTOISE
+	db 40, BLASTOISE
+	db 40, TOTARTLE
+	end_water_wildmons