[Dune] Release tarballs

[Christian Engwer]

Hi Jö,

> For "make dist" to work for grid-howto (and maybe grid-dev-howto, I'm not
> sure) I needed to checkout dune-web alongside all the other modules.
> Otherwise I get complaints about a missing "layout.wml" or something similar.

actually this is a bug in the module itself. We must have a
look. Actually no modules should include wml files anymore except
dune-web. The tarballs usually used the a simple layout, as they are
not published on the web site with the corresponding css files etc. in
place. Thus I expect the generated html files will look rather ugly.

I'll have a look.

Christian