- added transformation function parameter 'adjinfill' into a few normalizations nmbr, mnmx, retn, DPrt
- such as to allow changing default numeric infill from mean imputation to adjacent cell
- adjinfill parameter can be passed as True/False, defaults to False
- this parameter is redundant with what can be specified with assigninfill to return sets with adjacent infill
- but thought it might be beneficial to have option for customizing default infills applied prior to ML infill
- I have a hunch that adjacent infill may be better suited as a default imputation
- because of inherent stochasticity
- but don't have evidence so for now primary numeric normalization default remains mean imputation
- also added a few code comments for clarity for assignparam parameters in these normalization transforms