[Dune] release 2.6

[Andreas Dedner]

Hi.
Martin and I want to start with the release process next week. We need a
place to discuss the open issues, bugs etc. and there was the question
of helper scripts (I think from Ansgar?) and where to put them. How
about setting up a project Infrastructure/releases/ with a 2.6 branch.
The scripts can go into the releases project and discussion on the
actual release can be done in the issue tracker. Since it is possible to
link between issues/MR of different project having the discussion for
all core modules in one place would then be quite easy. I could open up
an separate issue for each core module in Infrastructure/releases to
cover discussions on open issues/bugs.

I don't seam to have permissions to add a project to infrastructures so
one of the owners would have to start it off.
Andreas