This reverts commit eb23730432aaeeef35b85feb013942175ae504f8, reversing
changes made to 1f0191190bcd9dfce903cf5af155ee114d00ac4b.
Only undo the permission changes
Conflicts:
Polygon_mesh_processing/examples/Polygon_mesh_processing/hole_filling_example_OM.cpp
Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Hole_filling/Weights.h
Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/fair_impl.h
Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/triangulate_hole.h
All non-ASCII files should be encoded in UTF-8. So far, the ZSH script
`Scripts/developer_scripts/detect_wrong_encoding` detects wrong encoding
in source/header files of include/, src/, and doc/.