Add Dubious Disc Salesman

This adds the Dubious Disc Salesman to Cinnabar Pokemon Centre. I chose this area because it's late in the game and it seemed a bit iffy to constantly have to go with Pokemon Centres not in towns. Cinnabar has some connection to Silph, so it makes more sense than just balancing.

There are probably improvements that could be made (eg. a quote as you buy) but the salesman code is surprisingly brittle so I'd rather not break stuff for hours for something that already works perfectly fine.

text/CinnabarPokecenter.asm

@@ -19,3 +19,44 @@ _CinnabarPokecenterText3::
 	para "I think it's"
 	line "worth a try!"
 	done
+
+_PoryZSalesmanText1::
+	text "MAN: Whoa there,"
+	line "kid! Long time"
+	cont "no see!"
+	
+	para "My uncle works for"
+	line "SILPH CO., and he"
+	cont "got me some top"
+	cont "secret data on the"
+	cont "next PORYGON!"
+	
+	para "Tell you what."
+	line "You can get a"
+	cont "copy for ¥2100."
+	cont "What do you say?"
+	
+	done
+
+_PoryZSalesmanNoText::
+	text "Huh? Are you sure?"
+	line "It's your big"
+	cont "chance!"
+	done
+
+_PoryZSalesmanNoMoneyText::
+	text "You'll need more"
+	line "money than that!"
+	done
+
+_PoryZSalesmanText2::
+	text "MAN: I'm not"
+	line "liable for any"
+	cont "bugs in that code!"
+	done
+
+_PoryZBagFull::
+	text "Hey, your bag's"
+	line "full! Can't sell"
+	cont "you anything like"
+	cont "that!"