Clean up configuration.md links.
Clean up configuration.md links.

They were a mess. Fixes #1058

d0ugal/mkdocs,lukfor/mkdocs,waylan/mkdocs,waylan/mkdocs,jimporter/mkdocs,jimporter/mkdocs,lukfor/mkdocs,lukfor/mkdocs,waylan/mkdocs,mkdocs/mkdocs,d0ugal/mkdocs,mkdocs/mkdocs,mkdocs/mkdocs,d0ugal/mkdocs,jimporter/mkdocs