[16.0] stock_storage_type : allow new product refactor

[jbaudoux]

During migration to v16, some refactoring was required as some concepts had been integrated in odoo.

To support more advanced decision for "allow new product", an "allow new product" had been added on the capacity.

The standard "allow new product" on the storage category is not used.

This design forced to create several package types while conceptually it is still the same package type. Also you cannot express a proper condition based on what it being moved (like based on other product attribute or based on the quantity) as you are limited to the package type as unique condition.

I propose to drop that complexity on the capacity and use by default the odoo standard storage category "allow new product".
And then on the storage category, add a more advanced mode where you can define a storage category condition (like the storage location sequence condition) and an "allow new product".

cc @rousseldenis