Recipe finder's heuristic needs tweaking

[dwmuller]

The current heuristic for ranking possible recipe lists is far too simple, favoring recipes with fewer steps, then with fewer deficit items (without regard for item value).

Better heuristics should take into account value and/or rarity of items consumed, and of remaining deficit items. Possibly also recipe execution item (for refiner recipes), although that information is not currently available in the program. Note that some items may not have values, making his a little difficult to figure out.