* Feature - Added template to customize the 'Products compare' widget content.
* Tweak - Tested compatibility up to WC 8.2.
* Tweak - Tested compatibility up to WP 6.4.
* Fix - Fixed 'Template Overrides' info in the 'System Status Report'.
* Dev - Added filter hook `woocommerce_products_compare_selected_products`.
* Dev - Refactored widget class by extending the class `WC_Widget`.
* Dev - Deprecated class `WC_Products_Compare_Widget`.
* Dev - Changed the plugin namespace to `KoiLab\WC_Products_Compare`.
* Dev - Updated the minimum requirements to WC 3.7, WP 4.9, and PHP 5.6