Those issues were detected by the compilation flag `-Wconversion` of g++-5.3. That changes the ABI of CGAL_ImageIO.
* The non-documented WITH_VTK is no longer supported. * The function CGAL::Image_3::read_vtk_image_data has been replaced by a global function. * Added Mesh_3/examples/Mesh_3/mesh_3D_gray_vtk_image.cpp
- Replacement of assert() by CGAL_assertion()