Fixed a bug in AbstractManager.
Bugfix and formatting.
Improved Item Display to be usable in the Quest Diary.
Item Client Display : 
* Moved the requirements verification from the ItemStack to the Item.
* Bugfix on empty spell.
Bugfix: Typo in method name.
Bugfix in server ItemStack class
Updated the shared keys.
#17 : Added normal item rewards in the Quest model.
Server.Element now takes world in constructor parameter.
* Added a preloadData method to Client.SharedElement.
* Added (bool) Client.SharedElement.isLoaded
Added a Utils.plural utility method.
Updated the Client.ItemManager.test method
#9 : Added normal Item reward. (Choice Item is still to do)