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/0224-Implement-ensureServerConversions-API.patch

@@ -1,27 +0,0 @@
-From aae8be84bd2b26b5a192bd5f1b6cdc2eb220d051 Mon Sep 17 00:00:00 2001
-From: Aikar <aikar@aikar.co>
-Date: Wed, 4 May 2016 22:43:12 -0400
-Subject: [PATCH] Implement ensureServerConversions API
-
-This will take a Bukkit ItemStack and run it through any conversions a server process would perform on it,
-to ensure it meets latest minecraft expectations.
-
-diff --git a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemFactory.java b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemFactory.java
-index 49ebad22e..eb6987338 100644
---- a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemFactory.java
-+++ b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemFactory.java
-@@ -194,4 +194,11 @@ public final class CraftItemFactory implements ItemFactory {
-     public Color getDefaultLeatherColor() {
-         return DEFAULT_LEATHER_COLOR;
-     }
-+
-+    // Paper start
-+    @Override
-+    public ItemStack ensureServerConversions(ItemStack item) {
-+        return CraftItemStack.asCraftMirror(CraftItemStack.asNMSCopy(item));
-+    }
-+    // Paper end
- }
--- 
-2.15.1
-