Add support for date localization

[rain2o]

While trying to use this date picker, I've found it rather challenging to offer localized date formats, as I do everywhere else in my app. I believe the easiest way to accomplish this would be to add the LocalizedFormat plugin for dayjs.

An alternative option would be to allow a format function in lieu of a format string. So I could pass something like formatter={(value) => new Date(value).toLocaleDateString()}. This would offer more robust options in the long-term, but of course would require a bit more effort to introduce and maintain.