* Feature - Manage abandoned carts of registered and guest customers.
* Feature - Automate abandoned cart emails through AWeber.
* Feature - Recover abandoned carts by using a recovery link.
* Tweak - Remove older update notices on plugin activation.
* Tweak - Added compatibility with WC 4.0.
* Tweak - Added compatibility with WP 5.4.
* Fix - Fixed error when passing a callable as argument to the `empty()` function in PHP 5.4 and lower.
* Fix - Fixed incompatibility with PHP 5.2 due to the usage of short ternary operators.
* Dev - Set the minimum requirements to WC 3.0 and WP 4.4.
