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/Optimize-UserCache-Thread-Safe.patch

@@ -10,7 +10,7 @@ Additionally, move Saving of the User cache to be done async, incase
 the user never changed the default setting for Spigot's save on stop only.
 
 diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
-index 45d3dbde..ab793307 100644
+index 45d3dbde2..ab7933079 100644
 --- a/src/main/java/net/minecraft/server/MinecraftServer.java
 +++ b/src/main/java/net/minecraft/server/MinecraftServer.java
 @@ -0,0 +0,0 @@ public abstract class MinecraftServer implements ICommandListener, Runnable, IAs
@@ -23,7 +23,7 @@ index 45d3dbde..ab793307 100644
          // Spigot end
      }
 diff --git a/src/main/java/net/minecraft/server/UserCache.java b/src/main/java/net/minecraft/server/UserCache.java
-index 487fc11f..924dc63a 100644
+index 487fc11f1..924dc63a4 100644
 --- a/src/main/java/net/minecraft/server/UserCache.java
 +++ b/src/main/java/net/minecraft/server/UserCache.java
 @@ -0,0 +0,0 @@ public class UserCache {