NEW: new function to convert binary segmentation to trilinear. Include smoothing along centreline to remove step-effects (see issue #31)
NEW: new function to convert binary segmentation to trilinear. Include smoothing along centreline to remove step-effects (see issue #31)

Former-commit-id: d943bd296c14d0fe16b5275d248e81ef9e672bf2
Former-commit-id: d95e5063a397d6370f65cbd6bc4c8c39c2586188
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox