OPT: detect_vertebral_levels: working!
OPT: detect_vertebral_levels: working!

Former-commit-id: d77731f56afa352de53fafb847568e875bd4ef0a
Former-commit-id: 9435ab370f64903edaacd1847f98b0e50bfcff47
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox