return new tags in addNodes/addElements
It's handy to pass empty tag vector to model.mesh.addNodes/addElements api but it would be much better if it was possible to get the tags automatically assigned. (especially for addNodes if the new nodes are used to create new elements).
The implementation is trivial but the problem is that it would require an additional (return) argument that would break the existing c++ api. An option to remain compatible with the the existing api would be to allow the tag vector to be both input and output argument but that requires the introduction of a new mechanism in GenApi.py, I'm not sure it's worth it.