swapping color palettes #47

(feature suggestion)
For one of my projects i drew images with a fixed color palette which i want to be able to change on the fly. I kind of hacked this in by allowing matchPalette to accept another palette so that, after matching, it takes the colors of the second and not the first palette.

Example:
We have an image with a palette of three different colors ('#aaa', '#bbb', '#ccc').
Now we run

cq(image).matchPalette(['#aaa', '#bbb', '#ccc'], ['#f00', '#0f0', '#00f'])

And the returned image uses the second palette where '#aaa' was replaced by '#f00' etc.
Now, the way i did it was rather dirty and assumes that both palettes have the same length, maybe you can find a nicer way.

tl;dr: It would be cool to have a nice way to swap color palettes of an image.