Biotech no longer required, can be run without it

Updated Icon of XENO

Updated Preview Image

Gave the armour some offsets to make it better and worth the price to craft

Updated Sprites and preview image

Made it so items cost shadum horns

Fixed issue with shadum spawning muffalo stuff

- Added a new creature, Shadum.
- Fixed trading of nightshade faction
- Rebalanced Xeno to be playable
- Fixed other issues

Updated the clothing of the mercs to also include pants and a tshirt rather than just the armour

Fixed missing faction error