Cloning fix

This fixes #5771.

Looks like a benign version of the mininuke blocker.  Taking off the
item before removing it had the remover fail silently, rather than
deleting it from inventory.

That was depressingly easy.
Merge pull request #5772 from KA101/mutation-cloning-fix

Cloning fix
it be durgs, yessum
Adds high-end chemistry recipe to extract sugar from wood.
Merge pull request #5773 from Rivet-the-Zombie/aspirin-category-fix

Changes aspirin recipe category to 'drugs' instead of 'chemicals'.
Difficulty tweak.
Merge pull request #5774 from Rivet-the-Zombie/sugar-hydrolysis-from-wood

Adds high-end chemistry recipe to extract sugar from wood.