README.md's pairing note still said adn-monitor 2.0.0-rc.4 (server was on
2.5.6) — both projects' next release is 2.6, so set both sides now.
README_es.md never had this line, or any of the rest of README.md's
content beyond Acknowledgments (9 lines vs 92): translated the full file
so it matches structure and content, with docs/es/ links where a Spanish
page exists (server/development/testing.md doesn't yet, links to the
English page).
Rodrigo Pérez