nanshe/nanshe/expanded_numpy.py: In function, add_singleton_axis_pos, drop use of keyword argument for axis in all but one of the doctests.
nanshe/nanshe/expanded_numpy.py: In function, add_singleton_axis_pos, drop use of keyword argument for axis in all but one of the doctests.

jakirkham/nanshe,nanshe-org/nanshe,DudLab/nanshe,DudLab/nanshe,jakirkham/nanshe,nanshe-org/nanshe