YITH WooCommerce Gift Cards Premium 4.22.0

* New: added plugin shortcodes to the Elementor panel
* Fix: fixed an error with the non existing product object
* Dev: all strings escaped

* Tweak: display the pre-printed gift cards as a new label in the gift card table
* Fix: fixed a warning when saving a post meta
* Fix: fixed and issue in the presets template, global post deleted from the template

New: Support for WordPress 5.4
New: Support for WooCommerce 4.0
New: added new shortcode yith_gift_cards_user_table to display the current user gift card table
Tweak: added the categories metabox in the gift card products
Tweak: Included the expiration date and the customer email in the smart coupons convertion
Update: updated MPDF to 8.0.5
Update: updated .pot
Update: plugin framework
Update: Spanish language
Update: Italian language
Fix: fixed a gift card not generated with gift this product
Fix: fixed a little issue in the settings menu style
Fix: fixed the conversion of the dates that are saved manually in the gift cards panel
Fix: fixed Aelia integration when there are more than two gift cards in the order
Fix: added a plugin-fw dep to hide disable code generation field
Fix: fixed an issue with the gift this product add to cart from email button
Fix: fixed wrong options names to show shop logo before/after the gift card image correctly
Fix: fixed the possibility of add a gift card as coupon even if it's disabled or deleted
Fix: fixed the possibility of add a gift card as coupon even if it's disabled or deleted
Fix: show manage stock field after saving a gift card
Dev: minor css fix
Dev: minor changes
Dev: new filter 'yith_wcgc_admin_tabs_control'
Dev: added new condition to display the gift this product form directly
Dev: added some string changes and translations
Dev: added a check in the product-suggestion template
Dev: check if ywgc_data is an object in the JS
Dev: do not display arguments in the gift this product link if they are not needed
Dev: removed compatibilities with WooCommerce versions lower to 3.3.0
Dev: added an array check in the gift card presets template
Dev: delete the https in the template image
Dev: deleted Emogrifier class load