Preserve ICC color profiles

[urdh]

Currently, hakyll-images will discard all metadata except image orientation when transforming images, including any ICC color profile embedded within the image. This causes some images to shift noticeably in color after transformation.

It would be neat if hakyll-images could preserve the ICC color profile, though I realize this also means JuicyPixels would need to support ICC profiles for more formats than just bitmaps.

[LaurentRDC]

Hi Simon,
Thanks for reporting this issue!

Realistically, I don't have the time to work on this myself, but I am always happy to review pull requests.