Integration in 3D Slicer

I created a [new repository](https://github.com/MedicalImageAnalysisTutorials/SlicerMeshing) to use robust_hex_dominant_meshing in [3D Slicer] (https://www.slicer.org/)

There is currently a [discussion](https://github.com/Slicer/ExtensionsIndex/pull/1621) if it should be integrated in Slicer or not. It would be nice if you help answering some related question. 