remove distribution option from estimate_sigma, because only the Gaussian case is implemented
remove distribution option from estimate_sigma, because only the Gaussian case is implemented

vighneshbirodkar/scikit-image,rjeli/scikit-image,rjeli/scikit-image,vighneshbirodkar/scikit-image,vighneshbirodkar/scikit-image,rjeli/scikit-image,paalge/scikit-image,paalge/scikit-image,paalge/scikit-image