Merge branch 'add-ExternalData-management-system-2017.02.13' into 'master'

CMake/Utilities/ExternalData.cmake

CMake/Utilities/ExternalData_config.cmake.in

CMake/Utilities/imstkCheckFileExists.cmake

CMake/Utilities/imstkExternalData.cmake

CONTRIBUTING.md

Data/Testing/ExternalDataTest.txt.sha512

...ction_Arteries_aorta_iliac3_filledholes_hollow.veg.sha512

Data/artery/artery.config.sha512

Data/artery/artery.csv.sha512

Data/asianDragon/asianDragon.bou.sha512

Data/asianDragon/asianDragon.config.sha512

Data/asianDragon/asianDragon.obj.sha512

Data/asianDragon/asianDragon.veg.sha512

Data/biceps_zones/biceps_ct.veg.sha512

Data/biceps_zones/biceps_ct_zones.bou.sha512

Data/biceps_zones/biceps_ct_zones.config.sha512

Data/biceps_zones/biceps_ct_zones.veg.sha512

Data/cube/cube.obj.sha512

Data/cube/cube.ply.sha512

Data/cube/cube.png.sha512