[WISH] kanban view for products in purchase orders

[zeroheure]

Impacted versions: master

Steps to reproduce: add a purchase with some new products which you will create while typing

Current behavior: it is difficult to see which newly product need some work, and it is also impossible (AFAIK) to browse products related to a an order, and also to edit them in batch.

Expected behavior:

• add a kanban products view inside the purchase order, with next/previous buttons
• from the Purchase/Products menu, make it easy to filter products related to a purchase order

In small retail, it is common to discover new products from vendors when purchasing on the vendor website. Thus the purchase order in Odoo always contains new products. Problem is that it is difficult to see, from the order, which product record need more information.