OPT: register_to_template: added smoothing again
OPT: register_to_template: added smoothing again

Former-commit-id: a487c3b912207f711489dda98ee1967af9103875 [formerly 2a1bb1c87a68dc8257d5ba3f67a7c7831c72e6d6]
Former-commit-id: 4636690601bc8d5f10d76ce35f21458dd3f980c9
Former-commit-id: 47f0f5a129077dd71ad7af8a78bc7e1215b131b2
neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox