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/MagmaHideout_3F_2R/scripts.inc

@@ -3,7 +3,7 @@ MagmaHideout_3F_2R_MapScripts:: @ 823A3D4
 
 MagmaHideout_3F_2R_EventScript_23A3D5:: @ 823A3D5
 	trainerbattle 0, TRAINER_GRUNT_47, 0, MagmaHideout_3F_2R_Text_23A3EC, MagmaHideout_3F_2R_Text_23A4BB
-	msgbox MagmaHideout_3F_2R_Text_23A4EF, 6
+	msgbox MagmaHideout_3F_2R_Text_23A4EF, MSGBOX_AUTOCLOSE
 	end
 
 MagmaHideout_3F_2R_Text_23A3EC: @ 823A3EC