Added docs for update_mc_username command

GeoffreyApp/docs/source/getting_started.rst

@@ -67,6 +67,32 @@ Setup Settings
 **************
 To setup your ``settings.py`` for Geoffrey, checkout :ref:`django_settings`
 
+Enable Username Updates
+***********************
+Minecraft usernames in Geoffrey can be updated using the `update_mc_username` sub-command:
+::
+
+    python manage.py update_mc_username
+
+To handle username updates automatically , an external scheduling program should be used. Below is an example of how to
+do this with a Linux cron job:
+
+.. code-block:: bash
+
+    #!/bin/bash
+    PATH_TO_GEOFFREY_MANAGE=/home/geoffrey/django/manage.py
+    PATH_TO_VENV=/home/geoffrey/venv
+
+    source "$PATH_TO_VENV/bin/activate"
+
+    python $PATH_TO_GEOFFREY_MANAGE update_mc_username
+
+    deactivate
+
+The above script should be played in the appropriate `/etc/cron.` directory.
+
+
+