YITH WooCommerce Product Bundles Premium 2.4.0

* New - support to WooCommerce 3.6
* New - option to show the price of bundled items in Cart and Checkout when the option 'per item pricing' is enabled
* Fix - integration with YITH WooCommerce Multi Vendor
* Fix - support to YITH WooCommerce Dynamic Pricing and Discounts
* Fix - non-closed <a> tag in bundle widget
* Fix - stock status issue in combination with third-party plugins
* Fix - removed 'qty' css class in quantity buttons of bundled items to prevent issue with themes that customize the quantity buttons
* Update - plugin framework
* Update - language files
* Tweak - check if bundle is in cart, otherwise remove bundled items, if they are there
* Tweak - prevent notices with PHP 7
* Dev - added yith_wcpb_select_product_box_args filter
* Dev - added yith_wcpb_widget_before_product_title action

New - set minimum/maximum quantity of different items allowed in the bundle
Fix - stock status CSS class in single product page
Fix - issue when overriding default selection for variable attributes on hidden bundled items
Update - language files
Update - plugin framework
Tweak - removed '1x' label in title if the bundled item quantity is set to one

* New - support to WordPress 5.0
* Fix - YITH WooCommerce Role Based Prices integration
* Fix - failed add to cart operation when maximum limit value of bundle is set to zero
* Fix - style issues
* Update - plugin framework
* Update - language files
* Tweak - issue on displaying stock availability
* Dev - added yith_wcpb_customization_bundled_item_stock_html filter