NEW: added a flag for final interpolation
NEW: added a flag for final interpolation

Former-commit-id: ea104711c9f74fb338f8b63777743354c8df55d9
Former-commit-id: 0d21d4690a9803328f306a3abfc99acc1b6442df
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox