Add ability to catch entities with fishing

[ErikSzabo]

This PR adds a new entity loot type for fishing (or it can be added to other loot tables as well, it just didn't really make sense). The caught entity can be a vanilla entity (typically a mob) or a MythicMobs using the mythicmobs: prefix. Entity health, damage, and level can also be configured.

The vertical and horizontal velocities are also configurable for fishing but already have default values.

Example configuration in fishing.yml:

type: fishing
pools:
  rare:
    base_chance: 100
    selection_priority: 1
    loot:
      - type: entity
        entity: zombie
        name: "&6My Little Zombie"
        weight: 50
        health: 100
        damage: 100
        velocity:
          horizontal: 1.2
          vertical: 1.3
      - type: entity
        entity: mythicmobs:SkeletonKing
        weight: 50
        level: 10

[ErikSzabo]

Made those changes. Also enabled auto formatting in Intellij on save for the future :'D