5.0.0+1.19.4

What's Changed

~~How did we end up here?~~

Api is now in the api package. :tada: (I know very rare)
Remove TickingSpell in favor of adding ticking to Spell allowing for a cleaner implementation.
Added SpellEntity
Spells are now constructed without a caster.
Improve network usage by NebulaSpellManager and NebulaManaManager.
Added isEmpty check to Spell- and ManaManagers to easily check if a Manager has been created.
Added SpellType.Builder#parallelCast to let spells easily control if they can be cast in parallel.
Added SpellType.Builder#castability so that a spellType being able to be cast can be checked without creating a Spell. (This should done instead of overriding Spell#isCastable)
SpellManager#isCastable should NO LONGER check for the Manager. The Managers are independent of each other now! Use SpellType#isCastable or Spell#isCastable!

Spell#onEnd() is called when the spell ends.
Spell#stop() stops the spell.
Spell#interrupt() interrupts the spell, indicates that the spell didn't choose to stop, but is forced by death e.g.
Spell#getDuration() returns the amount of ticks a spell can survive before being stopped.
Spell#tick() is a tick method, do I need to explain what this is for?

Full Changelog: https://github.com/Dev0Louis/Nebula/compare/4.0.3+1.19.4...5.0.0+1.19.4