Bug#888712: netgen: Please update to newest package version 6.2.x

[Kurt Kremitzki]

Upstream has tagged 6.2.1802. I have a package for this ready, but it 
depends on my OCCT 7.2 package. Also, the Python bindings for 6.2.1802 
depend on pybind11 >= 2.2 which is only in experimental currently.