This removes a buggy conditional that checks if `related_label` is
available in translations before displaying the header for related
posts but this header already handle missing translation by using a
default string.
With this fix the header is displayed even if the translation for this
label isn't available.
Fix#900
- Jekyll ignore `/docs` and `/test` folders when using from root
- Update Staticman config to point to correct branch and data file location
- Replace `{{ base_path }}` references with `absolute_url` filter
- Update documentation
