Added new options:
- hide-vanilla-enchantments - to hide or show vanilla enchantment lore
- disable-enchanting-table - to toggle enchanting table usage
- disable-anvil - to toggle anvil usage
- disable-grindstone - to toggle grindstone usage
(Note, that custom enchanted item cannot be placed or used in anvil or grindstone)

Added command to replace equations for easier usage:
- /ef modify equation [key^] [equation*]
(key^ - existing equation key, equation* - new equation)

Fixed minor GUI bugs.