Refactored the galaxy model hierarchy.

Fixed the 1-D PSF convolution code for model and derivatives.
Added module for psf-related stuff.
Updated model PSF handling.
Refactored fitting workflow, added options to control bounds, derivative, radial profile and fitting method.

Fit using normalized parameters.

Updated fit plot to match the fixed PSF.
Added the non-quick noise evaluation from qbick.
Organized class and instance members of the fitting class.

Added bad fit flag.
Qbick back to scipy "quick' detrend for noise estimation.
Fixed qbick planes generator.
Only convolve model images with PSF if FWHM > 0.

Do not mask center of galaxy without PSF convolution.
Minimum boundaries = 1e-20.
Flagging bad fits (for now, only out of bounds).
Fixed bug when creating quick planes and masking the center of the galaxy.