Import of whoward's pick-n-mix DLL v18

Initial import (and successful build) pulled from whoward's pick-n-mix.
The source is based off SDK v1.0.2.21; the imported DLL source is v18.
The original can be found here:

http://www.picknmixmods.com/mods/603c3504-d224-4101-a5da-cd712fefd49d/mod.html