Recently I wanted to add Chuvash localization to the jQuery UI datepicker. Unfortunately, my pull request was rejected. The reason is that jQuery UI will be using Globalize framework: The jQuery Globalize framework relies on CLDR, so What is Unicode CLDR (Common Locale Data Repository)?

The Unicode CLDR provides key building blocks for software to support the world’s languages, with the largest and most extensive standard repository of locale data available. This data is used by a wide spectrum of companies for their software internationalization and localization, adapting software to the conventions of different languages for such common software tasks