[MERGE] mrp, etc: ease production order edition

Ease manufacturing order edition in allowing to edit in the tree view.
Consider that one manufacturing order = 1LN/SN and create back-orders
in case several of them should be produced in the same MO.
Ease definition of operations and their different steps by allowing to
do it in the same BoM screen.

joint work Simon Lejeune <sle@openerp.com>
joint work Arnold Moyaux <arm@odoo.com>
joint work William Henrotin <whe@odoo.com>
joint work =?UTF-8?q?R=C3=A9my=20Voet=20=28ryv=29?= <ryv@odoo.com>
joint work yhu-odoo <yhu@odoo.com>
joint work "Tiffany Chang (tic)" <tic@odoo.com>

task-2241471

closes odoo/odoo#52949

Signed-off-by: Simon Lejeune (sle) <sle@openerp.com>