gamedata :
[*]ClassicPlayer:some modification to fit with the item's optimisations.
[*]SpyPlayer: same as ClassicPlayer.
items:
[*]Cam : updated to fit with Item.
[*]EmptyItem : updated to fit with Item.
[*]Gun : updated to fit with Item.
[*]Item : Some optimisation. Added deleteItem(ClassicPlayer).
[*]Knife : updated to fit with Item.