nanshe/nanshe/registration.py: Check magnitude_delta_space_shift's value explicitly.
nanshe/nanshe/registration.py: Check magnitude_delta_space_shift's value explicitly.

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