Use compact memory format for uniform chunk section data.

Many chunk sections contain parts of their data that are the same for
every block they contain. In these cases we can save memory by saving
a single value instead of an array of 4096 copies of that value. Block light
and block data are most likely to be uniform followed closely by sky light
data. Block ids are far less likely to be uniform but give the largest
saving when they are. Because of this we use a compact format for every
part of the chunk. Memory saved from this technique will vary based on the
world but seems to be about 50% on normal Minecraft generated chunks.
[Bleeding] Ignore damage done by LivingEntity.damage(). Fixes BUKKIT-5666

This matches behavior previous to new damage event API of not throwing
events for plugin-triggered damage.
[Bleeding] Fix checks for non-living entities. Fixes BUKKIT-5667
Implement new getOnlinePlayers. Adds BUKKIt-5668
POM Changes
mc-dev imports
Skeleton API Implementations
Obfuscation Helpers
Spigot Configuration
Better Chunk Tick Selection
Crop Growth Rates
More Efficient Chunk Save Queue
Merge tweaks and configuration

This allows the merging of Experience orbs, as well as the configuration of the merge radius of items. Additionally it refactors the merge algorithm to be a better experience for players.
LongHash Tweaks
Async Operation Catching

Catch and throw an exception when a potentially unsafe operation occurs on a thread other than the main server thread.
View Distance

This commit allows the user to select per world view distances, and view distances below 3. Be wary of the issues selecting a view distance of 1 or 2 may cause!
Improved Timings System

Tracks nearly every point of minecraft internals and plugin events to give a good quick overview on what is causing TPS loss.
Fix Mob Spawning Relative to View Distance
Handle Null Tile Entities
Entity Activation Range

This feature gives 3 new configurable ranges that if an entity of the matching type is outside of this radius of any player, will tick at 5% of its normal rate.

This will drastically cut down on tick timings for entities that are not in range of a user to actually be "used".
This change can have dramatic impact on gameplay if configured too low. Balance according to your servers desired gameplay.