[Opm] Release 2020.04

[Joakim Hove]

Dear Opm community;

I have been appointed release manager for the 2020.04 release, this 
email is to inform about my plans for the release.


_Features to be included:_ The general principle is that everything 
which is merged at the time the release branches is created is included 
as part of the release. In the period between the creation of the 
release branches and the final release the release manager can choose to 
backport changes from the master branch to the release branch. This will 
be the release managers decision to make. All features to be included in 
the release must come via the master branches.

I have created a milestone "Release 2020.04" in all the GitHub 
repositories. You are encouraged to mark your PR's with this milestone, 
at least when the dates for creation of release branches draws near it 
is important that the PR's are marked. The way I interpret these 
milestones markers  is as follows:

 1. Before the release branches are created this is just a heads up to
    me that: "Joe developer want's this feature in the release".
 2. After the release branches are created I will watch the PR; if it is
    merged before the final release there are two possibilities:
     1. I decide to backport the feature to the release branch - in that
        case the "Backported 2020.04" label is added to the PR.
     2. I decide to not backport the feature to the release branch - in
        that case the PR will be removed from the "Release 2020.04"
        milestone.

I will create an issue on OPM simulators for a discussion of features 
which are "on the brink of being in included in the release".


_Important dates:_

 1. Creation of release branches: Wednesday 22.th of April
 2. Creation of release candidate 1. Friday 24.th of April
 3. Release canditate2 / final Friday 1.st of May
 4. (Absolute final release date: Friday 8.th of May)


_Thoughts about a release/testing:_ My thinking about the release is 
that it represents a fencepost in the continous stream of bugs and 
features, it is not realistic to try to guarantee "bug free" at release 
time. I see it as the release managers responsability to ensure that:

 1. Packages work - in "apt get / yum install" sense.
 2. All tests in opm-tests including Norne works.

If you want to ensure that other models of various kinds work you are 
responsible for testing them.


Let it roll!


Joakim