Add variants of templates that include the international font.

This adds a `:template-intl` route fot all templates (e.g. `/templates/wrapper-intl.html.erb`), which is the same as the regular version except that it includes fonts-intl.css (and fonts-intl-ie8.css).

This will need thorough browser testing to ensure we're not exceeding any size limits on a data-uri (the international font is 119k before base64 encoding).