Function render_html_with 

pub fn render_html_with(
    item: &DocItem,
    file_stem: &str,
    siblings: &[(String, String)],
    index_link: &str,
    table: &LinkTable,
) -> String

ADR-0089 Phase 5: render a single item page, rewriting intra-doc links against table. When called from the site driver, table is usually DocSite::link_table().