Feature/require cmake 3.13

We should create similar merge requests for all core modules (and beyond) before merging this.

Fixes #200 (closed)

added buildsystem label

mentioned in issue #200 (closed)

Before we can merge this, we have to remove Ubuntu 18.04 from our test farm. Probably we should replace it by Ubuntu 20.04, which is the latest LTS version of Ubuntu.

We don't need to remove 18.04, we could just install a more recent cmake version in the docker image. Or does this give a wrong impression about direct compatibility of dune in ubuntu versions?

Maybe we should also update the duneproject script that prints in the generated readme "cmake >= 2.8.12" or something similar.

added 1 commit

• 9e1f8a01 - Mention required CMake version as 3.13

Compare with previous version

changed milestone to %New CMake Build-System

resolved all threads

added 13 commits

• 9e1f8a01...30cbe040 - 10 commits from branch master
• 9c08beda - [cmake] Require CMake 3.13 or newer
• 35fa202d - [cmake] Drop code for outdated CMake versions
• d537a55c - Mention required CMake version as 3.13

Compare with previous version

merged

mentioned in commit 57bf1afe

mentioned in commit ca87fea2

mentioned in issue #199 (closed)