v2.1.1: Major bugs fixes and a QOL addition

Related to 0f14c56:

[+] Added option to drop the xp in the ground instead of receiving it directly, most useful to repair tools with mending. Use xp-drop on config.yml to activate this.

Related to aed1d4f:

[/] Fixed a duplication bug

[/] Fixed items being unusable after storing in a container (Chest, EnderChest...) and relogging on the server.

[/] Fixed a bug where relogging would cause an exception and make all items unusable.

• Next update will most likely contain a stacking option (being able to stack items into each other)

v2.1: Stopped using NBTAPI, Heavy changes on items.

[+] Update all stuff to latest version to make sure everything works on 1.20+

[-] Stopped using NBTAPI, started using PersistentDataContainer. Better compatibility and lighter.

[/] Fixed give and gift commands.

[/] Created messages and sounds for give command

[/] Fixed drop listener, could cause items to break.

[/] Cleaned up code and applied Single responsibility principle to WithdrawableItem (kind of 😄)