[ADD] point_of_sale: Getting daily sales statistics

https://docs.google.com/document/d/1mEoZpBGxeG1gjDGo-FoCgf--bBpOrqVD3jRz0AWGz40/edit?usp=sharing

point_of_sale/analyze/statistics.rst

@@ -1,3 +1,44 @@
 ==============================
 Getting daily sales statistics
-==============================
+==============================
+
+
+Point of Sale statistics
+========================
+
+On your dashboard, click on the **More** button on the point of sale you
+want to analyse. Then click on **Orders**.
+
+.. image:: media/statistics01.png
+    :align: center
+
+You will get the figures for this particular point of sale.
+
+.. image:: media/statistics02.png
+    :align: center
+
+Global statistics
+=================
+
+Go to :menuselection:`Reports --> Orders`.
+
+You will get the figures of all orders for all point of sales.
+
+.. image:: media/statistics03.png
+    :align: center
+
+Cashier statistics
+==================
+
+Go to :menuselection:`Reports --> Sales Details`.
+
+Choose the dates. Select the cashiers by clicking on **Add an item**. Then
+click on **Print Report**.
+
+.. image:: media/statistics04.png
+    :align: center
+
+You will get a full report in a PDF file. Here is an example :
+
+.. image:: media/statistics05.png
+    :align: center