add doc for date localisation

Introduce the twig Intl extension and make ref to the doc.

refs #272

source/development/index.rst

@@ -19,6 +19,7 @@ As Chill rely on the `symfony <http://symfony.com>`_ framework, reading the fram
     Routing <routing.rst>
     Menus <menus.rst>
     Message to users <flashbags.rst>
+    Localisation <localisation.rst>
     Database migrations <migrations.rst>
     Searching <searching.rst>
     Testing <make-test-working.rst>

source/development/localisation.rst

@@ -0,0 +1,29 @@
+.. Copyright (C)  2014 Champs Libres Cooperative SCRLFS
+   Permission is granted to copy, distribute and/or modify this document
+   under the terms of the GNU Free Documentation License, Version 1.3
+   or any later version published by the Free Software Foundation;
+   with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
+   A copy of the license is included in the section entitled "GNU
+   Free Documentation License".
+
+Localisation
+*************
+
+Date and time
+==============
+
+The `Intl extension <http://twig.sensiolabs.org/doc/extensions/intl.html>`_ is enabled on the Chill application. 
+
+You may format date and time using the `localizeddate` function : 
+
+.. code-block:: jinja
+
+   date|localizeddate('long', 'none')
+
+By default, we prefer using the `long` format for date formatting.
+
+.. seealso::
+
+   `Documentation for Intl Extension <http://twig.sensiolabs.org/doc/extensions/intl.html>`_
+      Read the complete doc for the Intl extension.
+