No documentation on Datepicker i18n?

No documentation on Datepicker i18n?

Hello.
I've have been trying to localize my datepicker to Swedish. I looked
in the docs but there appears to be no documentation on it, just an
example which I can't get to work.
The rest of the documentation is excellent so it's abit strange that
almost nothing is written about how to localize the datepicker. The
documentation needs to explain where to put the i18n folder if it's
needed. Right now that folder is in the development bundle, ideally
that folder should be in js-folder as well since I think people often
just grab the minified version (I know I do) and have to go digging
for the i18n files.
I put the i18n folder in my js-folder but I'm still having no luck. I
included the Swedish i18n-file and when looking at the code it appears
as if it's setting the datepicker to Swedish ($.datepicker.setDefaults
($.datepicker.regional['sv'])) but my datepickers are still in
English.
My datepicker code looks like this
$("#date_to").datepicker({
    dateFormat: 'yy-mm-dd',
    minDate: new Date(),
    onSelect: function(dateText, ui) {
        console.log(dateText);
    }
});
What do I need to do to get this to work?
Kindly,
Marcus
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