[ADD] inventory: new doc page about using inventory valuation (#502)

inventory/management/reporting.rst

@@ -7,5 +7,6 @@ Valuation Methods
    :glob:
 
    reporting/inventory_valuation_config
+   reporting/using_inventory_valuation
    reporting/valuation_methods_continental
    reporting/valuation_methods_anglo_saxon

inventory/management/reporting/using_inventory_valuation.rst

@@ -0,0 +1,77 @@
+=============================
+Using the inventory valuation
+=============================
+
+Inventory valuation refers to how you value your stock. It’s a very
+important aspect of a business as the inventory can be the biggest asset
+of a company.
+
+In this documentation, we will explain how the inventory valuation works
+in Odoo.
+
+Inventory valuation: the basics
+===============================
+
+Receive a product
+-----------------
+
+Each time a product enters or leaves your stock, the value of your
+inventory is impacted. The way it is impacted depends on the
+configuration of your product (more info here).
+
+Let’s take an example with a product - a table - configured with a
+*FIFO costing method* and an automated inventory valuation.
+
+I purchase 10 tables at a cost of $10.
+
+.. image:: media/use_inventory_valuation_01.png
+    :align: center
+
+When I’ll confirm the receipt of the products, the value of my inventory
+will be impacted. If I want to know what this impact is, I can click on
+the valuation stat button.
+
+.. tip::
+         The consignment feature allows you to set owners on your stock (discover
+         more about the consignment feature). When you receive products that are
+         owned by another company, they are not taken into account in your
+         inventory valuation.
+
+.. image:: media/use_inventory_valuation_02.png
+    :align: center
+
+.. note::
+         You need access rights on the accounting module to see that button.
+
+In this case, I can see that the 10 tables entered the stock for a total
+value of $100.
+
+.. image:: media/use_inventory_valuation_03.png
+    :align: center
+
+I can also easily access the accounting entry that has been generated
+(in case of automated inventory valuation).
+
+.. image:: media/use_inventory_valuation_04.png
+    :align: center
+
+Deliver a product
+-----------------
+
+In the same logic, when a table will be delivered, the stock valuation
+will be impacted and you will have access to a similar information.
+
+.. image:: media/use_inventory_valuation_05.png
+    :align: center
+
+The inventory valuation report
+------------------------------
+
+The summary of this is accessible via the inventory valuation report
+(accessible from *Inventory > Reporting > Inventory Valuation*). It gives
+you, product per product, the value of your stock. By clicking on the
+button *Inventory At Date*, you can have the same information for a
+past date.
+
+.. image:: media/use_inventory_valuation_06.png
+    :align: center