OPT: added choice to specify or not centreline file and uses biplane from scipy for smoothing intensity
OPT: added choice to specify or not centreline file and uses biplane from scipy for smoothing intensity

Former-commit-id: e414d2b07662ff6cb9c024c390dbfc361e1f1ae0 [formerly 822a90f209a3b6261fb11829c6deaea540c4b57e]
Former-commit-id: a219c4c35113f8ae60b544c9811b78ca1997e6ee
Former-commit-id: b7c88f15d9391dc5a21d7f011e442fcb939f43bd
neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox,neuropoly/spinalcordtoolbox