Merge remote-tracking branch 'vov/TortuosityModule'

* vov/TortuosityModule:
  Fix Tortuosity filter and make sure it passes the test
  Fix Tortuosity module compilation
  Move logic's tortuosity computation to a TubeTK filter - 2/2
  Move logic's tortuosity computation to a TubeTK filter - 1/2
  Add option to save the tortuosity arrays as an CSV file
  Enable deletion of spatial object nodes
  Enable run tortuosity button only when a valid node is present
Fix dimensions in ConvertTRE for TubeTK to TubeX conversion

Change-Id: I7171a5467d57954cd9146d45abcdce8411bc1a51
Merge pull request #359 from vovythevov/FixConvertTRE

Fix convert tre