Manage pricelists through a common configuration between sale and point_of_sale
Remove lots of technical fields
Improved Pricelist Flow
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if pricelists enabled (product.group_product_pricelist), two modes are proposed:
* basic(default): pricelists enabled, but only with basic rules
* advanced: pricelists enabled, but with advanced rules (product.group_sale_pricelist)
When pricelists are enabled, we can always access them through the menu OR access their product-targeted rules from the products/templates views.