[ADD] accounting: Record exchange rates at payments

https://docs.google.com/document/d/1XYljDvXD27s2v9w7T7yFKuMXJ79QUkKXwpLmQchYf9c/edit#

accounting/others.rst

@@ -9,5 +9,6 @@ Others
    others/analytic
    others/taxes
    others/adviser
+   others/multicurrencies
    others/reporting
    others/inventory

accounting/others/multicurrencies.rst

@@ -0,0 +1,10 @@
+========
+Overview
+========
+
+.. toctree::
+   :titlesonly:
+
+   multicurrencies/how_it_works
+   multicurrencies/invoices_payments
+   multicurrencies/exchange

accounting/others/multicurrencies/exchange.rst

@@ -0,0 +1,110 @@
+=================================
+Record exchange rates at payments
+=================================
+
+Overview
+========
+
+Any company doing international trade faces the case where the payments
+are in a different currency.
+
+After receiving their payments, you have the option to convert the
+amount into your company currency. Multi currency payment implies rates
+fluctuations. The rate differences are automatically recorded by Odoo.
+
+Configuration
+=============
+
+Enable multi-currencies
+-----------------------
+
+In the accounting module, Go to :menuselection:`Configuration --> Settings` 
+and flag **Allow multi currencies**, then click on **apply**.
+
+.. image:: media/exchange_rate03.png
+   :align: center
+
+Configure the currency rates in :menuselection:`Configuration --> Currencies`.
+Write down the rate and make sure the currency is active.
+
+.. image:: media/exchange_rate02.png
+   :align: center
+
+In this document, the base currency is **Euro** and we will record payments
+in **Dollars**.
+
+.. image:: media/exchange_rate08.png
+   :align: center
+
+.. tip:: 
+    You can automatically fetch the currency rates from the **European
+    Central Bank** or from **Yahoo**. Please read the document : 
+    :doc:`how_it_works`.
+
+Configure your journal
+----------------------
+
+In order to register payments in other currencies, you have to **remove
+the currency constraint** on the journal. Go to the accounting
+application, Click on **More** on the journal and **Settings**.
+
+.. image:: media/exchange_rate06.png
+   :align: center
+
+Check if the **Currency** field is empty or in the foreign currency in which
+you will register the payments. If a currency is filled in, it means
+that you can register payments only in this currency.
+
+.. image:: media/exchange_rate10.png
+   :align: center
+
+Record a payment in a different currency
+========================================
+
+In the **Accounting** application, go to :menuselection:`Sales --> Payments`. 
+Register the payment and indicate that it was done in the foreign currency. Then
+click on **confirm**.
+
+.. image:: media/exchange_rate05.png
+   :align: center
+
+The journal entry has been posted but not allocated.
+
+Go back to your invoice (:menuselection:`Sales --> Customer Invoices`) and click on
+**Add** to allocate the payment.
+
+.. image:: media/exchange_rate04.png
+   :align: center
+
+Record a bank statement in a different currency
+===============================================
+
+Create or import the bank statement of your payment. The **Amount** is in
+the company currency. There are two complementary fields, the **Amount currency**, 
+which is the amount that was actually paid and the **Currency** in which it was paid.
+
+.. image:: media/exchange_rate07.png
+   :align: center
+
+When reconciling it, Odoo will directly match the payment with the right
+**Invoice**. You will get the invoice price in the invoice currency and the
+amount in your company currency.
+
+.. image:: media/exchange_rate09.png
+   :align: center
+
+Check the exchange rate differences
+===================================
+
+Go to :menuselection:`Adviser --> Journal Entries` and look for the **Exchange difference**
+journal entries. All the exchange rates differences are recorded in it.
+
+.. image:: media/exchange_rate01.png
+   :align: center
+
+.. tip::
+    The Exchange difference journal can be changed in your accounting settings.
+
+.. seealso::
+    * :doc:`../../bank/reconciliation/configure`
+    * :doc:`../../bank/reconciliation/use_cases`

accounting/others/multicurrencies/how_it_works.rst

@@ -0,0 +1,3 @@
+=====================================
+How is Odoo's multi-currency working?
+=====================================

accounting/others/multicurrencies/invoices_payments.rst

@@ -0,0 +1,3 @@
+=======================================================
+How to manage invoices & payment in multiple currencies
+=======================================================