NEW: mode weight for the similarity computation, similarity weight for the label fusion
NEW: mode weight for the similarity computation, similarity weight for the label fusion

Former-commit-id: d61c0d050b35db2316fd0b431b2aea870366878d
Former-commit-id: 81dd2cf8cc72a3e84a20bb5115cdf2bb5766b713
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox