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/AbandonedShip_HiddenFloorRooms/scripts.inc

@@ -138,7 +138,7 @@ AbandonedShip_HiddenFloorRooms_EventScript_238DE3:: @ 8238DE3
 
 AbandonedShip_HiddenFloorRooms_EventScript_238DF3:: @ 8238DF3
 	lockall
-	msgbox AbandonedShip_HiddenFloorRooms_Text_238DFE, 4
+	msgbox AbandonedShip_HiddenFloorRooms_Text_238DFE, MSGBOX_DEFAULT
 	releaseall
 	end