Fixes and improvements for custom enchantments library
- PlayerChangedArmorEvent is now fired more consistently
- Introduced PlayerChangedHeldItemEvent
- Added new enchant trigger KILL_ENTITY
- Added new enchant trigger HOLD_ITEM
- Fixed bug where enchants with a space in their name would not be included when calling EnchantRegistry#getEnchants(ItemStack)
- Added methods for Title Case and camelCase in FormatUtils
- Added method to get structure data block type from StructureBlock