OPT: register_to_template: back to all_labels=1 due to rotation (see #610)
OPT: register_to_template: back to all_labels=1 due to rotation (see #610)

3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox