Convert attributes in HTML spec into API-docs in simple repository API#1

EpicWink wants to merge 2 commits into

simple-repo-apiEpicWink/packaging.python.org:simple-repo-apifrom

simple-repo-api-html-attr-apidocEpicWink/packaging.python.org:simple-repo-api-html-attr-apidocCopy head branch name to clipboard