Document the Windows Subsystem for Linux (#2319)

Added guide for installing AiiDA on Windows sub-system for Linux

docs/source/install/details/os.rst

@@ -95,4 +95,27 @@ If you want to manually start the RabbitMQ server you can use:
 
     /etc/init.d/rabbitmq start
 
-For more information, or if you run into trouble, please refer to the RabbitMQ :ref:`troubleshooting section<installation_rabbitmq>`.
+For more information, or if you run into trouble, please refer to the RabbitMQ :ref:`troubleshooting section<installation_rabbitmq>`.
+
+
+Windows Subsystem for Linux (Ubuntu)
+------------------------------------
+
+The guide for Ubuntu above can be followed but there are a few things to note:
+
+#. The `windows native RabbitMQ <https://www.rabbitmq.com/install-windows.html>`_
+   should be installed and started,
+   since the version in WSL Ubuntu 18.04 does not work properly.
+
+#. Linux services under WSL are not started automatically.
+   To start the PostgreSQL service, type the command below in the terminal::
+
+     sudo service postgresql start
+
+#. There is a `known issue <https://github.com/Microsoft/WSL/issues/856>`_ in WSL Ubuntu 18.04 where the timezone is not
+   configured correctly out-of-the-box, which may cause problem for the database. 
+   The following command can be used to re-configure the time zone::
+
+     dpkg-reconfigure tzdata
+
+#. The file open limit may need to be raised using ``sudo ulimit -n 2048`` (default is 1024), when running tests.