S K-edge normalization
This change is to accommodate the case (encountered at the sulfur K-edge) where only the sum of 'n' and 'p' ROI can be normalized against '0'.
Changes
- depreciate
inspect_plane_fitting
and replace it withinspect_ff_fitting
- framework to work with different flat field normalization function
- implement 2D polyline normalization
- compute
np_mean
directly in process
Edited by Loïc Le Guyader