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/maps/objects/BillsGarden.asm

@@ -0,0 +1,12 @@
+BillsGarden_Object:
+	db $03 ; border block
+
+	def_warp_events
+	warp_event  6, 17, BILLS_HOUSE, 1
+	warp_event  7, 17, BILLS_HOUSE, 1
+
+	def_bg_events
+
+	def_object_events
+
+	def_warps_to BILLS_GARDEN

data/maps/objects/BillsHouse.asm

@@ -2,8 +2,9 @@ BillsHouse_Object:
 	db $d ; border block
 
 	def_warp_events
-	warp_event  2,  7, LAST_MAP, 1
-	warp_event  3,  7, LAST_MAP, 1
+	warp_event  2,  9, LAST_MAP, 1
+	warp_event  3,  9, LAST_MAP, 1
+	warp_event 11,  0, BILLS_GARDEN, 1
 
 	def_bg_events
 
@@ -11,5 +12,6 @@ BillsHouse_Object:
 	object_event  6,  5, SPRITE_MONSTER, STAY, NONE, 1 ; person
 	object_event  4,  4, SPRITE_SUPER_NERD, STAY, NONE, 2 ; person
 	object_event  6,  5, SPRITE_SUPER_NERD, STAY, NONE, 3 ; person
+	object_event 11,  1, SPRITE_MONSTER, STAY, NONE, 4 ; nidorino
 
 	def_warps_to BILLS_HOUSE

data/maps/objects/CinnabarLab.asm

@@ -16,5 +16,6 @@ CinnabarLab_Object:
 
 	def_object_events
 	object_event  1,  3, SPRITE_FISHING_GURU, STAY, NONE, 1 ; person
+	object_event 11,  6, SPRITE_SCIENTIST, WALK, ANY_DIR, 2 ; person
 
 	def_warps_to CINNABAR_LAB