Improved i18n support for FormItStateOptions and FormItCountryOptions

Add Swedish translation for states and countries.
Change FormItStateOptions to use the system setting cultureKey as default value to the "country" option.
Add the "country" option to FormItCountryOptions with cultureKey as default value.
See bug #9992 (http://bugs.modx.com/issues/9992) for an issue with the default values that is set in the module code.