REF: updated extract_centerline using module from smooth_centerline
REF: updated extract_centerline using module from smooth_centerline

Former-commit-id: 4df865a1ce54bee9ced3f6ee6162b8f631177e76
Former-commit-id: 0d31757797dadd59e196f8ef2075ef8fc67ce77d
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox