Rename all files in data/pokedex/entries/

Some people suggested this would be a good idea, and make management of
the files easier. I'm inclined to agree.

data/pokedex/entries/nidoqueen.asm

@@ -0,0 +1,10 @@
+; NidoqueenPokedexEntry: ; 0x18232e
+	db "DRILL@" ; species name
+	dw 403, 1320 ; height, weight
+
+	db   "The hard scales"
+	next "that cover its"
+	next "strong body serve"
+	page "as excellent"
+	next "protection from"
+	next "any attack.@"