MTLB: add function to be able to use the function segmenting the CSF
MTLB: add function to be able to use the function segmenting the CSF

Former-commit-id: 1e5385a35a6ba1cbbeebc1a295bb59964c4f98bb
Former-commit-id: 6478ab7d001a06e28877efd5959239c93b1484d3
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox