Interface for MRtrix filter_tracks
Updates for MRtrix FilterTracks interface
Ran make check-before-commit
DTK track_merge interface
Fix for MRtrix-TrackVis conversion of tracks have been normalized or filtered
Added auto tests
Updated CHANGES, removed genfile, added docstrings, updated tests for DTK and MRtrix
Merge remote-tracking branch 'origin/pr/848'

Conflicts:
	CHANGES