[ADD] inventory: How to process delivery orders in two steps (pick + ship)?

https://docs.google.com/document/d/1qvEm6TEWQQSfZV8AjE4yJUB11qf28OBVtVYRrws5-_g/edit

inventory/delivery/two_steps.rst

@@ -1,3 +1,133 @@
 ==========================================================
 How to process delivery orders in two steps (pick + ship)?
-==========================================================
+==========================================================
+
+Overview
+========
+
+When an order goes to the shipping department for final delivery, Odoo
+is set up by default to utilize a **one-step** operation: once all goods are
+available, they are able to be shipped in a single delivery order.
+However, your company’s business process may have one or more steps that
+happen before shipping. In the **two steps** process, the items in a delivery
+order are **picked** in the warehouse and brought to an **output location** for
+**shipping**. The goods are then shipped.
+
+In order to accomplish a **Pick + Ship** delivery in Odoo, there are a few 
+necessary configuration steps. These steps create an additional
+location, which by default is called **Output**. So, if your warehouse’s
+code is ``WH``, this configuration will create a location called
+``WH/Output``. Goods will move from ``WH/Stock`` to ``WH/Output`` in the first
+step (picking). Then, they move from ``WH/Output`` to ``WH/Customers`` (in the
+case of sales orders) in the second step (shipping).
+
+.. note::
+    Check out :doc:`inventory_flow` to determine if this inventory flow is the
+    correct method for your needs.
+
+Configuration
+=============
+
+Allow management of routes
+--------------------------
+
+Odoo configures movement of delivery orders via the **routes**. Routes
+provide a mechanism to chain different actions together. In this case,
+we will chain the picking step to the shipping step.
+
+To allow management of routes, go to :menuselection:`Configuration --> Settings`.
+
+Ensure that the radio button **Advanced routing of products using
+rules** is checked.
+
+.. image:: media/two_steps05.png
+   :align: center
+
+Click on **Apply** at the top of the page to save changes (if you needed to
+check the radio button above).
+
+.. note::
+    If you checked option **Advanced routing of products using rules**
+    you may need to activate **Manage several locations per warehouse** if it
+    wasn’t activated beforehand.
+
+Configure warehouse for Pick + Ship
+------------------------------------
+
+To configure a **Pick + Ship** move, go to 
+:menuselection:`Configuration --> Warehouses` and edit
+the warehouse that will be used.
+
+For outgoing shippings, set the option to **Bring goods to output
+location before shipping (Pick + Ship)**
+
+.. image:: media/two_steps03.png
+   :align: center
+
+Create a Sales Order
+====================
+
+Install the **Sale** if it is not the case, and 
+create a sales order with some products to deliver.
+
+Notice that we now see ``2`` transfers associated with this sales order
+in the **Delivery** stat button above the sales order.
+
+.. image:: media/two_steps01.png
+   :align: center
+
+If you click on the **2 Transfers** stat button, you should now see two
+different pickings, one with a reference **PICK** to designate the
+picking process and another with a reference **OUT** to designate the
+shipping process.
+
+.. image:: media/two_steps04.png
+   :align: center
+
+Process a Delivery
+==================
+
+How to Process the Picking Step?
+--------------------------------
+
+Ensure that you have enough product in stock, and go to 
+**Inventory** and click on the **Waiting** link under the **Pick** kanban card.
+
+.. image:: media/two_steps06.png
+   :align: center
+
+Click on the picking that you want to process.
+
+Click on **Reserve** to reserve the products if they are available.
+
+Click on **Validate** to complete the move from **WH/Stock** to **WH/Output**.
+
+This has completed the picking step and the **WH/PICK** move should now show
+**Done** in the status column at the top of the page. The product has
+been moved from **WH/Stock** to **WH/Output** location, which makes the product
+**available for the next step** (Shipping).
+
+How to Process the Shipping Step?
+---------------------------------
+
+Go to **Inventory** and click on the **# TO DO** link under the
+**Delivery Orders** kanban card.
+
+.. image:: media/two_steps02.png
+   :align: center
+
+Click on the picking that you want to process.
+
+Click on **Validate** to complete the move from **WH/Output** to the
+customer (Click **Apply** to assign the quantities based on the
+quantities listed in the **To Do** column)
+
+This has completed the shipping step and the **WH/OUT** move should now show
+**Done** in the status column at the top of the page. The product has
+been shipped to the customer.
+
+.. todo::
+    link to these sections when they will be available
+    -  Process Overview: From sales orders to delivery orders
+
+    -  Process Overview: From purchase orders to receptions