Called whenever a players shield is disabled. This is mainly caused by
attacking players or monsters that carry axes.
The event, while similar to the PlayerItemCooldownEvent, offers other
behaviour and can hence not be implemented as a childtype of said event.
Specifically, cancelling the event prevents the game events from being
sent to the player.
Plugins listening to just the PlayerItemCooldownEvent may not want said
sideeffects, meaning the disable event cannot share a handlerlist with
the cooldown event.
Cryptite