Use correct color space for image inverstion (#4350)
Use correct color space for image inverstion (#4350)

The previous version of color inversion was done in `linearRGB` space
and produced the incorrect results (inverted image was too white/"blown
out").  This forces the filter to be calculated in the correct `sRGB`
color space.
amyrebecca/Panoptes-Front-End,amyrebecca/Panoptes-Front-End,zooniverse/Panoptes-Front-End,amyrebecca/Panoptes-Front-End