Eliminate stop variable

[MrCsabaToth]

This can help if there will be reorderings and we don't have to update these indexes manually which is error prone
This would require a custom ruby plugin: https://stackoverflow.com/questions/26073090/how-to-retrieve-the-current-post-index-number-in-jekyll
But that would require our own build on GitHub, such as github action, or Travis CI: https://stackoverflow.com/questions/53215356/jekyll-how-to-use-custom-plugins-with-github-pages