Spectral processing functions

swectral.functions.snv(data)	SNV (Standard Normal Variate) function.
swectral.functions.snv_hyper(data)	SNV (Standard Normal Variate) function for image pixel spectrum correction in SpecPipe pipelines.
swectral.functions.minmax(data)	MinMax (MinMax Normalization) function.
swectral.functions.minmax_hyper(data)	MinMax (MinMax Normalization) function for image pixel spectrum correction in SpecPipe pipelines.
swectral.functions.aucnorm(data)	AUC (Area Under Curve) normalization function.
swectral.functions.aucnorm_hyper(data)	AUC (Area Under Curve) normalization function for image pixel spectrum correction in SpecPipe pipelines.