Issue #1887: Equipped items do not emit sounds

Added playing of sounds for equipped items (at this moment only for lights).

Signed-off-by: Lukasz Gromanowski <lgromanowski@gmail.com>
Why is there a DrawState_Nothing check here? It shouldn't be needed. If a weapon is unequipped or the shield is hidden (showCarriedLeft/showWeapons), then sounds will be stopped properly, since removeIndividualPart() is used.