Added polish language files

git-svn-id: https://plugins.svn.wordpress.org/woocommerce-advanced-free-shipping/trunk@951634 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added polish language files

git-svn-id: https://plugins.svn.wordpress.org/woocommerce-advanced-free-shipping/trunk@951635 b8457f37-d9ea-0310-8a92-e5e31aec5664
Fixed 'french' to 'polish' in readme

git-svn-id: https://plugins.svn.wordpress.org/woocommerce-advanced-free-shipping/trunk@951636 b8457f37-d9ea-0310-8a92-e5e31aec5664