+ Fixed challenges being able to be moved around.
+ Removed the (s) in item names in challenges.
+ Fixed some heads (e.g sheep, parrot, horse) not showing up in the sellhead menu.
+ Fixed colour codes in sellhead menu not being translated.
+ Added an optional reward-string option in challenges.yml, so that you can choose a custom reward title to be shown when hovering your cursor over a challenge.
+ Improved the looting system.
+ Fixed further sellhead calculations.