Restore wpsc_get_visitor_meta filter
Was in previous releases
Removed todo from comment related to meta get filter
Remove  from WPSC_Countries::_create_region_code_by_region_id_map(), as it is no longer used.
restored 3.8.13.3 pre-filters to customer meta
restore 3.8.13.3 filter to allow override of customer id
Merge pull request #1156 from JeffPyeBrook/pr-issue-1149-missing-filter

Restore wpsc_get_visitor_meta filter
Checkout page user interface issues
* Fix issue where shipping state does not change when shipping calculator drop down changes
Put current customer meta values into hidden fields on checkout page just in case store owner hides fields on checkout forms.  This allows any JavaScript actions that have depend on the availability of specific meta items to work properly if the store administrator hides any of the fields in the checkout forms.
* Shipping state/region elements visibility was being changed when billing country was being changed.  Change billing state/region visibility when shipping country changes instead.

Should resolve issues reported in #1144