[Dune] Update of the official Homepage / dunedesign.png

[Christoph Grüninger]

Hi Oliver,
I think that dunedesign.png is comparable to organigrams on some 
corporate websites or the overview plan in some public authorities. You 
should get a first impression of the rough structure. Additionally some 
(module) names are mentioned and their relationships are sketch so you 
could recognize them later. It is not intended as a global register.

> If I need DG methods,
> Newton solvers, mortar assemblers etc., how would these pictures tell me
> where to find it?
>
> Attached is an illustration I use in my talks on Dune.  I find that one more
> informative (which doesn't mean it cannot be improved).

Your criticism is legitimate but I don't see the improvement from your 
illustration over dunedesign. I can't tell where to find DG methods and 
Newton solvers neither. I like the symbolic stacking over your arrows 
but that's a personal taste.

Nevertheless I think you have a good point. We should think about a page 
where the modules, grids, discretizations etc. are described and what 
they contain. Now we have some of these informations on /dune.html, 
/doc/devel/features.html and /doc/doxygen.html. I would merge and 
clarify these informations either on /dune.html or 
/doc/devel/features.html and let the website revamp team take over this 
task.

Have a nice weekend
Christoph