Merge branch '32-add-update-section-in-the-manual-for-1-2-3' into 'master'

Resolve "Add update section in the manual for 1.2.3"

Closes #32

See merge request fusiondirectory/user-manual!26

source/update/supported/1.2.2-to-1.2.3.rst

+Migrate FusionDirectory from 1.2.1 to 1.2.2
+===========================================                                       
+
+New Depot Configuration
+^^^^^^^^^^^^^^^^^^^^^^^
+
+.. warning::
+
+   The repositories have been cleaned and reorganized please update
+   your configuration accordingly
+
+   :ref:`debian-repository-label`.
+
+   :ref:`rpm-repository-label`.
+
+.. warning::
+
+    The gpg keys for FusionDirectory and Argonaut have been renewed
+    so you need to install the new keys for the packages to install
+    correctly
+
+    :ref:`gpg-keys-label`.
+
+Upgrade FusionDirectory first
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Upgrade FusionDirectory core package before other ones to avoid
+dependencies errors:
+
+.. code-block:: shell
+
+   apt-get install fusiondirectory
+
+Upgrade FusionDirectory schema package too.
+
+.. code-block:: shell
+
+   apt-get install fusiondirectory-schema
+
+Enjoy :)

source/update/supported/index.rst

@@ -6,5 +6,6 @@ Supported version
 .. toctree::
    :maxdepth: 2
 
+   1.2.2-to-1.2.3.rst
    1.2.1-to-1.2.2.rst
    1.2-to-1.2.1.rst