OPT: register_to_template: fixed issue #681
OPT: register_to_template: fixed issue #681

Former-commit-id: e63648730b4b8b568f6c267dd2d6de52a3a644c1
Former-commit-id: 7ea14fe977d272cdc743ed194b4c60c10c7c4a1d
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox