DevTools: Generate Changelog

[JuKu]

Add a Plugin which can generate a Changelog with all changed files since last version based on github tag.

Changelog should contain:

• closed issues
  • based on label, "Bug" --> "Bugfix: ", "feature" --> "new feature: "
  • append issue number and link
• List with Contributors (which have pushed commits or PRs)
• List with changed Template files (for compatibility check)
• List with all changed files

Maybe we can automatically commit this changelog file: https://docs.gitlab.com/ee/api/repository_files.html

[JuKu]

Interesting links:

• https://gist.github.com/arnold-almeida/209795
• https://stackoverflow.com/questions/1552340/how-to-list-only-the-file-names-that-changed-between-two-commits