`product_uom_id` is not in the allowed fields for stock.quant
when in inventory mode. See `_get_inventory_fields_create` method
in stock.quant for more details.
* You can know integrate with different forecasting mechanisms.
As a consequence integration with stock_demand_estimate is moved
to a new module (mrp_multi_level_estimate).
* As agreed by the authors, the module is re-licensed to LGPL-3.