Use the newest connect-fonts and connect-fonts-opensans

@jrgm - mind reviewing this one?

* Fix the problem with Russian (ru) using the default font. It now uses Cyrillic (though the request is still for /fonts/ru/<font_name>)
* Add Swedish (sv)
* Add Slovak (sl)
* Re-alias Portuguese (pt) to Spanish (es)
* Make sure Brazilian Portuguese (pt_BR) uses Spanish (es)

fixes #3029