Merge branch 'ma/doc-diff-doc-vs-doctor-comparison'

Dev support update to make it easier to compare two formatted results from our documentation. * ma/doc-diff-doc-vs-doctor-comparison: doc-diff: add `--cut-header-footer` doc-diff: support diffing from/to AsciiDoc(tor) doc-diff: let `render_tree()` take an explicit directory name Doc: auto-detect changed build flags