Clean up comments

Base data: types uniquely lacked a comment; items on one line; distinguish unknowns
Dex entries: don't imply that pointers don't exist

data/pokemon/dex_entries/sandshrew.asm

@@ -1,10 +1,10 @@
-; SandshrewPokedexEntry: ; 0x182184
 	db "MOUSE@" ; species name
 	dw 200, 260 ; height, weight
 
 	db   "It prefers dry,"
 	next "sandy places"
 	next "because it uses"
+
 	page "the sand to"
 	next "protect itself"
 	next "when threatened.@"