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/lapras.asm

@@ -0,0 +1,10 @@
+; LaprasPokedexEntry: ; 0x1cc0cd
+	db "TRANSPORT@" ; species name
+	dw 802, 4850 ; height, weight
+
+	db   "This gentle"
+	next "#MON loves to"
+	next "give people rides"
+	page "and provides a ve-"
+	next "ry comfortable way"
+	next "to get around.@"