Add support for keeping a spatially varying PSF for the image by using the fixed decorrelation afterburner correction (i.e. the decorrelation afterburner noise whitening is evaluated for one position of the matching kernel only, practically at the center of the image).

Construct a corrected spatially varying PSF by keeping the polynomial spatial solution and applying the correction to the fixed PSF component bases (images). Justification argument: We expect that the spatial variation of the PSF is small, so the variations of the corrections would be small too: so the spatial variaton of the PSF plus a spatially varying correction would be second order small.