DOC: sct_registe_multimodal -p option changed. Tested
DOC: sct_registe_multimodal -p option changed. Tested

Former-commit-id: 64153764d26d2c5fc5a03ff8ab2d52092ab50813 [formerly 107c3f26c9698952114f39f2123a4fb58b9d8093]
Former-commit-id: 11544e270255345de6e6383b137b1272695096e5
Former-commit-id: 926da2ed26f7d8026f78e6ff2e8cec6969bdea0d
neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox