Add PathfinderGoalTame for diff visibility.
Implement Horse API. Adds BUKKIT-4424

API has been added to interface with Horses and to modify their inventories. Horse entities will now be recognized with the type EntityType.HORSE, and will no longer be UNKNOWN.

HorseJumpEvent, EntityDamageEvent, and EntityTameEvent are all correctly fired for horses.

This commit fixes BUKKIT-4393.
Spigot
EMC POM changes
Misc EMC Changes

Only spawn 1 ocelot ever from eggs.
Load custom permissions before plugins
Unload plugins after everything else
Color name tags to match list
Make Durability enchant scale 0-80% reduction on Armor damage (up to level 5)
Zombies break down doors on normal
Update inventory on block place/interact cancellation
Anti Dupe

Remove CraftBukkit "Feature" of ItemStack's having infinite use if less than 0 stack size.
Blocks most cases of < 0 itemstack dupe bugs
Mob Spawning Events

Add 2 events for better control of mob spawning (Natural and Spawners) This allows us a much more powerful control over spawning and improve performance
PlayerUseItem Event

This lets us control when an item is consumed and change the item.
EMC Anvil Tweaks

Make Items not have a repair cost increase due to Anvil usage.
Renaming is only 5 levels, combines include free renames.
Hidden Item Meta

This adds the ability to store hidden metadata in item lore.

Simply set a line to "&&::META" and every blank line before, that line, and every line after will be hidden from view on the client.

for example, you can set &&::META on line 20, and there will not be 19 blank lines before it.
Then you can store Data on 21+

Also adds a &&::SHINY tag to send a fake enchantment aura if it does not exists.
Must be set before META
NIOM - NIO Manager

Alternative to Netty
improve the existing network manager using Blocking NIO instead of IO (more effecient code)
Writes use a direct memory buffer for less copying, and more stable memory usage.

Reimplement Low Priority Queue
Optimized PacketQueue System that supports instant send notification to the writer thread
Removed packet queue walking since it will very unlikely ever be hit now.
Writer thread will now sleep longer until notified
Network threads are no longer interrupted every tick, letting them sleep as much as possible
Persistent Meta API

This adds an API for getting and setting PERSISTENT Metadata
Meta data can be stored on Worlds, Entities, Chunks and at a Block level.
Meta is is provided in a simple Map/List setup and does not expose raw NBT access.
Chunk Save Reattempt

We commonly have "Stream Closed" errors on chunk saving, so this code should re-try to save the chunk in the event of failure and hopefully prevent rollbacks.
Keep certain items on death API

This adds a getItemsToKeep to PlayerDeathEvent that can be modified for what item a player should keep upon death.

This can be used for never-to-be-dropped items.
Anvil Event

Fire an event for anvil usage
ArrowHitBlock Event
Entity Spawn Events

These events fire any time an entity is added/removed to the world, so we do not
have to check multiple locations for entities being added/removed from the world.
Precise timings
Show 1/10s TPS averages
EntityShootBowEvent consumeArrow API