It is now needed to precompute inventories. Workflow has a new transition.

I believe the test was wrong from the beginning? It does not seem to match the comments.

- Test case where new stock in lesser than old stock
- Test recalculation of inventory
- Test full inventories
- Test `getTotalQuantity` and `getTotalPrice` methods

Almost working test, Inventory API still does not process properly.

Had I not done that before? How did it worked? Weird. Maybe just changed the configuration on the Portal Type ?

I am unsure if they should not instead be in the delivery movement group, that way we might be able to discard my change to ERP5Site and get rid completely of this inventory movement thing.

Also: add `getTotalQuantity`. Why?

…and delete unused `z_catalog_stock_list_without_delete_for_inventory_virtual_movement`