Gets and sets currencies that you want to support on your site.
You can set the currencies that you want your site to support. These are the currencies that are displayed in the currency conversion element and used to convert currencies in your Wix Store.
The currency codes used must exist in the array returned by the getAllCurrencies()
function.
Note: For SiteSettings functions to work, your site must contain a Wix Stores page including the currency conversion element.