When a product has a safety stock in an area, and the current stock is
below safety, but there are moves in the future, mrp_multi_level does
not compute an immediate action to get back to the safety stock.
This PR changes this behavior: when the mrp_moves are considered, before
processing the first move in the future, we insert a resupply action to
rebuild the safety stock.
We also add some refactoring in the process:
* add extension point on the wizard to compute the quantity to reorder
(so we can choose in a separate module whether to rebuild safety stock
or not)
* add extension point on the wizard to get the date at which the safety
stock must be rebuilt (defaults to today)
* make the code of the wizard symetric between the groupes and non
grouped configuration
For each MRP Parameter, we will calculate its supply method based on the procurement rules path. We will go back in the rules until we find that the action is "buy" or "manufacture", or until the action is "Pull From" or "Pull & Push" and the supply method is "Take from Stock".
This means we will show what the latest rule is if we were to do a procurement. Although it would be possible that the final action does not end up being executed if stock already exists in one of the intermediate locations.
demand moves have the same date it can happen that the supply is
effectively ignored if considered as staring move of the
grouping and there are more groups to be done after it.
A test case include in this fix depicts in detail the
the problem and ensures no regression.
* 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.
