Breaking changes:

* Moved several classes from "alexiil.mc.lib.attributes.item.impl" to "alexiil.mc.lib.attributes.item.compat":
    * FixedInventoryVanillaWrapper
    * FixedInventoryViewVanillaWrapper
    * PartialInventoryFixedWrapper (and renamed it to InventoryFixedWrapper)

Additions:
    * Added a new class: SidedInventoryFixedWrapper, which:
        * Extends InventoryFixedWrapper
        * Implements vanilla minecraft's SidedInventory interface.

Bug Fixes:

* Fixed a crash when exposing a InventoryFixedWrapper to a hopper.
* Fixed SlotFixedItemInv not working properly if the current stack is not valid for 
