UpgradeableSpawners - Levels 4.15.15

+ Improved: Spawner spawn event for 3rd party stacking plugins

- Fixed: Order of entities from entities.yml

- Fixed: Hide item attributes

- Fixed: Display of spawned entity with no-conditions enabled

- Fixed: Issue with stack knockback and other plugins

- Fixed: Entity type of vanilla spawner upon placement silktouch
- Fixed: Make monsters stacked despawn
+ Added: Option to kill whole stack

  # Kill the whole stack, if one entity dies?
  kill-stack: false

- Fixed: Error on folia with entity merge and area limit

+ Changed: Provide spawn reason for entity spawning

- Fixed: Folia support

+ Improved: Reduce amount of block state calls

- Fixed: Spawners spawning inside blocks in some setups - 2

- Fixed: Spawners spawning inside blocks in some setups

+ Added: 1.21 Support

+ Added: Option to only stack entities from spawners

    # Only stack entities that were spawned by an upgradeable spawner?
    only-spawner: true

- Fixed: Dont merge stacks in non spawner worlds

- Fixed: Argument translations for /spawner admin give

+ Added: Merge entities into stacks (entities.yml)

    # Merge entities into one stack
    merge:
      # Merge entities every specified interval.
      # Can be disabled by setting interval to something lower than 1.
      interval_time: 30s

- Fixed: Butcher mode drops

+ Added: Support for 1.20.5

+ Added: /spawner admin killall
+ Added: Options for butcher mode:

      butcher-mode:
        # Only supports UpgradeableHoppers: https://www.spigotmc.org/resources/69201
        hopper:
          # Require an upgradeablehopper to be placed underneath the spawner before butcher mode can be activated?
          required: false
          # Should loot be dropped, if the upgradeable hopper is full?
          drop-loot: true