Changes:
Revamped anvil support, custom enchantments with anvils are now completely seamless.
Added ability to add custom enchantments to items through anvils.
Added ability to edit the maximum level vanilla enchantments can be combined to in anvils (anvil.yml).
Added support for anvils on 1.12.
Added options to toggle now custom enchantment books can be applied.
Improved performance with HELD and EFFECT_STATIC.
WATER_WALKER and LAVA_WALKER no longer works in spectator mode.
Fixed error related to updating worn armor.