Drop shadow not ported from base game's update

[Daniel Wong]

the drop shadow effect was never ported from the base game, which improves readability in NVL mode

If possible we should make it toggleable, but default to ON (i'm not sure if that's possible)

*check_game
menu_waveon
shadedistance 3,3  ;< This function
;mov %UMINEKOEND,50
mov %ispatched,0
mov %UMINEKOPATCH,0

Todo:

• Add to master script
• Add to voice-only script

Also See #83