Make sure certain countries are required to fill in state/ province

[davidmosterd]

Improvement on #2711. In some cases we know it to be required; so we could use the input value of country to make the field required in some cases like the US and Canada.

WooCommerce has this solved rather elegant: ​https://github.com/woocommerce/woocommerce/tree/master/i18n

Though the JS part might be something custom; the definition of countries and states should not be all over the place?

Any thoughts?

[ryelle]

This isn't a very high priority issue — we can revisit if there are reports of sponsors with invalid addresses.