YITH WooCommerce Added to Cart Popup Premium 2.17.0

* New: Support for WooCommerce 4.4
* New: Support for WordPress 5.5
* Update: Plugin framework
* Update: Language files
* Dev: New filter 'yith_wacp_hide_mini_cart'
* Dev: New filter 'yith_wacp_continue_shopping_text'

* Update: Plugin framework
* Update: Language files
* Fix: Compatibility issue with WooCommerce All Products For Subscriptions plugin
* Fix: Popup responsive style

* New: Support for WooCommerce 4.0
* New: Support for WordPress 5.4
* New: Greek translation
* Update: Plugin framework
* Update: Language files
* Fix: Prevent fatal error "Call to a member function get_formatted_name() on boolean"
* Fix: Discount row visible also if discount amount is zero
* Fix: Empty popup after removing last product
* Tweak: Close popup with "ESC" key