WooCommerce Postcode Address Validation 2.11.3

* Fix - Prevent SmartyStreets "Unknown address" errors when changing a previously validated address to a different valid address

* Misc - Drop support for PHP v5.2: PHP v5.3 is now the minimum supported version
* Misc - Update SkyVerge plugin framework to version 5.3

* Fix - Prevent some versions of Google Chrome or other browsers from auto-completing the address lookup input field
* Dev - Add filters to change the active provider or toggle a provider's availability
* Dev - Add filters to dynamically alter the list of supported countries of each provider
* Misc - Add support for WooCommerce 3.5