ENH: Release of SlicerRT 0.9.0: New Contour Comparison and Patient Hiera...

...rchy modules (latter deactivated for 4.2 but will be re-instated in 4.3). One-up quantitative layout in DVH module. Fixed Contour node labelmap resampling (coordinate systems/voxel cenerpoint issue). Many other bugfixes. See more info at https://www.assembla.com/code/slicerrt/subversion/changesets/compare/586..736