v2.0.0

• This version of the plugin was tested and works on Prestashop v8.1.* only.
• Fix the problem who prevents the merchant to add Nuvei Payment plan to the product in Prestasho v8.1.*.
• Fix the problem where the client can combine ordinary product with Nuvei Rebilling product.
• In case the plugin cancel to add a product to the Cart, and there is error, show first error message.
• Removed old commened parts of code.
• Removed an hook not working in Prestashop 8.1.*.