Add options to reference

Author: aclark4life

docs/source/ref/utils.rst

@@ -12,7 +12,7 @@ following parts can be considered stable.
 ``parse_uri()``
 ===============
 
-.. function:: parse_uri(uri, db_name=None, test=None)
+.. function:: parse_uri(uri, db_name=None, test=None, options=None)
 
     Parses a MongoDB `connection string`_ into a dictionary suitable for
     Django's :setting:`DATABASES` setting.
@@ -35,5 +35,8 @@ following parts can be considered stable.
     - Use ``test`` to provide a dictionary of settings for test databases in
       the format of :setting:`TEST <DATABASE-TEST>`.
 
+    - Use ``options`` to provide a dictionary of connection options to PyMongo.
+      These will be merged with options specified in the URI.
+
     But for maximum flexibility, construct :setting:`DATABASES` manually as
     described in :ref:`configuring-databases-setting`.