[1.8.x] Fixed #24281 -- Improved docs for timezone handling for auto_now and auto_now_add

Thanks djbug for the report and Aymeric Augustin and Carl Meyer for the
review.

Backport of 8119876d4a from master

docs/ref/models/fields.txt

@@ -510,6 +510,15 @@ Any combination of these options will result in an error.
     ``True`` will cause the field to have ``editable=False`` and ``blank=True``
     set.
 
+.. note::
+    The ``auto_now`` and ``auto_now_add`` options will always use the date in
+    the :ref:`default timezone <default-current-time-zone>` at the moment of
+    creation or update. If you need something different, you may want to
+    consider simply using your own callable default or overriding ``save()``
+    instead of using ``auto_now`` or ``auto_now_add``; or using a
+    ``DateTimeField`` instead of a ``DateField`` and deciding how to handle the
+    conversion from datetime to date at display time.
+
 ``DateTimeField``
 -----------------
 

docs/topics/i18n/timezones.txt

@@ -9,13 +9,13 @@ Time zones
 Overview
 ========
 
-When support for time zones is enabled, Django stores date and time
+When support for time zones is enabled, Django stores datetime
 information in UTC in the database, uses time-zone-aware datetime objects
 internally, and translates them to the end user's time zone in templates and
 forms.
 
 This is handy if your users live in more than one time zone and you want to
-display date and time information according to each user's wall clock.
+display datetime information according to each user's wall clock.
 
 Even if your Web site is available in only one time zone, it's still good
 practice to store data in UTC in your database. One main reason is Daylight