OPT: msct_parser: now display name of file if it does not exist
OPT: msct_parser: now display name of file if it does not exist

Former-commit-id: d90f04a718f1d124f9d412a9155ebb76c97ea504
Former-commit-id: f33e496f74e0723f08d2c601ecd1a739fd167c56
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox