Fixed a bug that allowed players to obtain trade items from the Witch Doctor UI without extracting them.

This is mostly a behind-the-scenes update, I refactored the WD UI's code and fixed a bug while I was at it. The bug would sometimes give players old versions of their scrolls when closing the UI, so any cost they paid for cures or slot extensions would be lost. Now the scroll is immediately updated when a change occurs.
Also, you can now shift-click scrolls into the WD UI.

Fixed the default indentation in strings.yml so that deleting the comment symbols immediately forms correct YML. Additionally expanded the tips at the top of the file to be more helpful. This should help people who want to translate the plugin.

Clarified how item costs need to be formatted in the config file.
Villagers are now killed instead of removed, this automatically frees up any workstations and beds they occupied.

It was brought to my attention that there were no XP rewards for trading with villager scrolls. Now they exist and they are even configurable. By default, they have the vanilla value of 3-6.
Note that this means you'll need to update your config file accordingly.

This was supposed to be included in the last update.

• Reworked permissions so that more things are configurable (details are in the readme on GitLab). Most notably, boxedvillagers.* no longer exists (replaced by boxedvillagers.admin, which grants all permissions) and all permissions are false by default.