BUG: sct_register_pipeline: **work in progress** adapting the pipeline to the new versions of register_to_template and register_multimodal
BUG: sct_register_pipeline: **work in progress** adapting the pipeline to the new versions of register_to_template and register_multimodal

Former-commit-id: 4158449efecb6100629ce5749dd86b4e0803e0b1 [formerly 429ac014bdcacdcb6033b8aaca3bd49c5ba67f52]
Former-commit-id: 933b99037b1183a53e98bf9f3ef9844816ac4239
Former-commit-id: 2ebde06e4915d7b1d93ad08e740b4754c410b3ee
neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox