Checklist for new version

[marcverhagen]

Always do the following:

• [ ] Run python -m utilities.make_documentation
• [ ] Update documentation if needed
• [ ] Make sure docs/manual/index.html is versioned
• [ ] Check documentation in docs and test it before publishing it and merging into master.
• [ ] Update README.md
• [ ] Update VERSION
• [ ] Update CHANGELOG.md
• [ ] Run tests and regression tests
• [ ] Merge to master branch
• [ ] Add version tag to repository by creating a new release