fixes#1362
Ignoring qty_available for phantom products prevents double counting the
qty_available of components.
Creating planned orders for phantom products is simpler than recursively
exploding phantom BOMs. This also makes it easier to analyze the planning data
generated by the MRP calculation.
* keept description of planned orders verbose.
* make it translatable in most cases.
* while grouping demand include the product in the description.
* add `origin` field not mrp moves and planned orders. Fill it
with top level demand origin.
* Planned Order release and due date become required.
* Add button to Product MRP Area to update MOQ from Supplier Info.
* Link Manufacturing Orders with Planned Orders.
* Allow Mrp Inventory Procure Wizard to be used from other models.
* Make MRP Inventory creation more extensible.
* Main Supplier computation (v13 requires explicit False definitions).
* 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.
