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/electrode.asm

@@ -0,0 +1,10 @@
+; ElectrodePokedexEntry: ; 0x1b8f19
+	db "BALL@" ; species name
+	dw 311, 1470 ; height, weight
+
+	db   "The more energy it"
+	next "charges up, the"
+	next "faster it gets."
+	page "But this also"
+	next "makes it more"
+	next "likely to explode.@"