The source project of this merge request has been removed.
[bugfix] make vtkFunction work with Dune 2.4.1
The backport core/dune-grid@d430a25d
to dune-grid 2.4.1 clashes with the work-around from commit
1a6da6a4, i.e. the vtkFunction adaptor.
To be compatible with Dune 2.4 and 2.4.1, this commit replaces
vtkFunction by a forwarding wrapper when using dune-grid 2.4.1 or newer.
fixes #6 (closed)