BUG: register_to_template: fixed missing return variable
BUG: register_to_template: fixed missing return variable

Former-commit-id: 2487ee5fa303b72fd57f15f7a15070879958419f
neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox