OPT: now possibility to choose the registration method for the first iteration of sct_register_multimodal: using SliceReg or using antsRegistration
OPT: now possibility to choose the registration method for the first iteration of sct_register_multimodal: using SliceReg or using antsRegistration

3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox