BUG: sct_straighten_spinalcord: now possible to use relative path (issue #365)
BUG: sct_straighten_spinalcord: now possible to use relative path (issue #365)

Former-commit-id: c9084381a9d387e5a82ca1b468c1da8efc65d3e6
Former-commit-id: 3fb390482cbe54711f8554a315fc0719fa680940
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox