#8 Allow weight to be spread when matching multiple categories

[Patrick Schmitz]

E.g., for color, need to spread out weight when matching multiple colors in one entry/row. Need to allow control in config. Need to support several models
1) Ignore - all get equal and high weight
2) Reduce - all get equal and moderate weight
3) Distribute Even - divide weight up by number matched
4) Distribute Descending - Divide weight by number matched, but then assign more weight to early matches than to later ones.
Color seems to need 4, in which something is described as "White, with red pattern and green spots". Here, the color match relevance is mostly on white, with some weight on red and minimal on green.