Add release for version 3.1.3

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

HISTORY.rst

@@ -1,4 +1,4 @@
-3.1.3 (2018-09-26)
+3.1.3 (2018-09-27)
 ==================
 * Make sure template API renders in non US languages.
 * Fix user groups view.

docs/releases/3.1.3.rst

@@ -0,0 +1,84 @@
+===============================
+Mayan EDMS v3.1.3 release notes
+===============================
+
+Released: September 26, 2018
+
+* Make sure template API renders in non US languages.
+* Fix user groups view.
+* Add no results help text to the document type -> metadata type
+  association view.
+* Expose the Django INSTALLED_APPS setting.
+* Add support for changing the concurrency of the Celery workers in the
+  Docker image. Add environment variables MAYAN_WORKER_FAST_CONCURRENCY,
+  MAYAN_WORKER_MEDIUM_CONCURRENCY and MAYAN_WORKER_SLOW_CONCURRENCY.
+
+Removals
+--------
+
+* None
+
+Upgrading from a previous version
+---------------------------------
+
+
+If installed via Python's PIP
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Remove deprecated requirements::
+
+    $ curl https://gitlab.com/mayan-edms/mayan-edms/raw/master/removals.txt | pip uninstall -r /dev/stdin
+
+Type in the console::
+
+    $ pip install mayan-edms==3.1.3
+
+the requirements will also be updated automatically.
+
+
+Using Git
+~~~~~~~~~
+
+If you installed Mayan EDMS by cloning the Git repository issue the commands::
+
+    $ git reset --hard HEAD
+    $ git pull
+
+otherwise download the compressed archived and uncompress it overriding the
+existing installation.
+
+Remove deprecated requirements::
+
+    $ pip uninstall -y -r removals.txt
+
+Next upgrade/add the new requirements::
+
+    $ pip install --upgrade -r requirements.txt
+
+
+Common steps
+~~~~~~~~~~~~
+Perform these steps after updating the code from either step above.
+
+Migrate existing database schema with::
+
+    $ mayan-edms.py performupgrade
+
+Add new static media::
+
+    $ mayan-edms.py collectstatic --noinput
+
+The upgrade procedure is now complete.
+
+
+Backward incompatible changes
+=============================
+
+* None
+
+Bugs fixed or issues closed
+===========================
+
+* `GitLab issue #513 <https://gitlab.com/mayan-edms/mayan-edms/issues/513>`_ Unicode problem on GET '/api/templates/main_menu/' with german translation
+
+.. _PyPI: https://pypi.python.org/pypi/mayan-edms/

docs/releases/index.rst

@@ -22,6 +22,7 @@ versions of the documentation contain the release notes for any later releases.
 .. toctree::
    :maxdepth: 1
 
+   3.1.3
    3.1.2
    3.1.1
    3.1