dedner authored Oct 19, 2021 and Praetorius, Simon committed Oct 22, 2021

comment out CMP0087 NEW cmake policy because it fails on some CI runners

Fix CI yml file - the 2.7 test will not work anymore

export the first vtk writer (unstructured vtk) still very crude

improve testvtk.py script

[bugfix] added missing 'unkown' to 'DataTypes' to_string

added lists for enum to allow for iteration which help with the export topython