adds constants, cleans up callstd and msgbox code

* adds some constants for standard script names and messagebox types
* replaces some callstd calls with msgbox calls where equivalent
* replaces msgbox and callstd calls using raw digits with versions that use the constants

data/maps/MtPyre_4F/scripts.inc

@@ -3,7 +3,7 @@ MtPyre_4F_MapScripts:: @ 8231BC8
 
 MtPyre_5F_EventScript_231BC9:: @ 8231BC9
 	trainerbattle 0, TRAINER_ATSUSHI, 0, MtPyre_5F_Text_231BE0, MtPyre_5F_Text_231C08
-	msgbox MtPyre_5F_Text_231C24, 6
+	msgbox MtPyre_5F_Text_231C24, MSGBOX_AUTOCLOSE
 	end
 
 MtPyre_5F_Text_231BE0: @ 8231BE0