WooCommerce 2.1 compatibility fixes

git-svn-id: https://plugins.svn.wordpress.org/weight-based-shipping-for-woocommerce/trunk@856222 b8457f37-d9ea-0310-8a92-e5e31aec5664
Allowed country selection feature

git-svn-id: https://plugins.svn.wordpress.org/weight-based-shipping-for-woocommerce/trunk@859651 b8457f37-d9ea-0310-8a92-e5e31aec5664