Optimize Hoppers

- Lots of itemstack cloning removed. Only clone if the item is actually moved
- Return true when a plugin cancels inventory move item event instead of false, as false causes pulls to cycle through all items.
  However, pushes do not exhibit the same behavior, so this is not something plugins could of been relying on.
- Add option (Default on) to cooldown hoppers when they fail to move an item due to full inventory
- Skip subsequent InventoryMoveItemEvents if a plugin does not use the item after first event fire for an iteration

Spigot-Server-Patches/IllegalPacketEvent.patch

@@ -6,7 +6,7 @@ Subject: [PATCH] IllegalPacketEvent
 Fired for invalid data from players that represents hacking attempts
 
 diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
-index 0191a9af..45a50602 100644
+index 0191a9af2..45a50602b 100644
 --- a/src/main/java/net/minecraft/server/PlayerConnection.java
 +++ b/src/main/java/net/minecraft/server/PlayerConnection.java
 @@ -0,0 +0,0 @@ import org.bukkit.inventory.CraftingInventory;