Every language now carries its own `locales/rn/<lang>.json` with the
roughly 600 strings the webmail catalog does not have, so settings,
sign-in, files, calendar and push screens no longer fall back to
English.
Terms and the form of address follow each language's vendored webmail
catalog, and plural messages use the language's own CLDR categories.
Wording that had no precedent in the catalog would benefit from a
native speaker's review.
Linus Rath
67935d2edc