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/Item-canEntityPickup.patch

@@ -5,7 +5,7 @@ Subject: [PATCH] Item#canEntityPickup
 
 
 diff --git a/src/main/java/net/minecraft/server/EntityInsentient.java b/src/main/java/net/minecraft/server/EntityInsentient.java
-index 5ea9f309..89e87836 100644
+index 5ea9f3097..89e878365 100644
 --- a/src/main/java/net/minecraft/server/EntityInsentient.java
 +++ b/src/main/java/net/minecraft/server/EntityInsentient.java
 @@ -0,0 +0,0 @@ public abstract class EntityInsentient extends EntityLiving {
@@ -22,7 +22,7 @@ index 5ea9f309..89e87836 100644
                      this.a(entityitem);
                  }
 diff --git a/src/main/java/net/minecraft/server/EntityItem.java b/src/main/java/net/minecraft/server/EntityItem.java
-index 6593fc63..99dbb139 100644
+index 6593fc633..99dbb1393 100644
 --- a/src/main/java/net/minecraft/server/EntityItem.java
 +++ b/src/main/java/net/minecraft/server/EntityItem.java
 @@ -0,0 +0,0 @@ public class EntityItem extends Entity implements HopperPusher {
@@ -34,7 +34,7 @@ index 6593fc63..99dbb139 100644
      private String g;
      private String h;
 diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftItem.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftItem.java
-index a17a537d..1df17f09 100644
+index a17a537d6..1df17f09b 100644
 --- a/src/main/java/org/bukkit/craftbukkit/entity/CraftItem.java
 +++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftItem.java
 @@ -0,0 +0,0 @@ public class CraftItem extends CraftEntity implements Item {