ENH: Add SlicerDMRI remote module

See http://slicerdmri.github.io/

The goal is to make Slicer core leaner and ultimately create a
SlicerDMRI extension

This remote module provides the following modules removed in previous
commits:

FiberBundleToLabelMap (Scripted)
DICOM2FullBrainTractography (Scripted)

TractographyDisplay (Loadable)
TractographyInteractiveSeeding (Loadable)

DiffusionTensorScalarMeasurements (CLI)
DiffusionWeightedVolumeMasking (CLI)
DWIJointRicianLMMSEFilter (CLI)
DWIRicianLMMSEFilter (CLI)
DWIToDTIEstimation (CLI)
DWIUnbiasedNonLocalMeansFilter (CLI)
DTIImportExport (CLI)
TractographyLabelMapSeeding (CLI)
FiberBundleLabelSelect (CLI)
FiberTractMeasurements (CLI)

Note that the following plugins and modules are not yet integrated
into SlicerDMRI:

ResampleDTIVolume (CLI)
ResampleScalarVectorDWIVolume (CLI)
DICOMDiffusionVolumePlugin (DICOM plugin)

Additionally, the following MRML nodes are still living in Slicer core,
they will ultimately be moved out when the infrastructure will support
it:
vtkMRMLDiffusionImageVolumeNode
vtkMRMLDiffusionTensorDisplayPropertiesNode
vtkMRMLDiffusionTensorVolumeDisplayNode
vtkMRMLDiffusionTensorVolumeNode
vtkMRMLDiffusionTensorVolumeSliceDisplayNode
vtkMRMLDiffusionWeightedVolumeDisplayNode
vtkMRMLDiffusionWeightedVolumeNode

Co-authored-by: Jean-Christophe Fillion-Robin <jchris.fillionr@kitware.com>

From: Isaiah Norton <inorton@bwh.harvard.edu>

git-svn-id: http://svn.slicer.org/Slicer4/trunk@24855 3bd1e089-480b-0410-8dfb-8563597acbee