* Added Guidedfilter to avoid color shift
* Various improvment to avoid color shift
* Small change to mint maxt
* local adjustments avoid color shift: reduce memory usage by width * height * 8 byte if Soft Radius > 0
* Remove StopWatch
* local adjustments avoid color shift: speedup for last loop
* cleanups
* one more cleanup
* Added checkbox Munsell correction only - uniform perceptual lab
* Refine some settings
* Clean-up - other small refinement
Co-authored-by: Ingo Weyrich <heckflosse67@gmx.de>