[1.6.x] Fixed #21372 -- Corrected docs regarding translating LANGUAGES.

Corrected LANGUAGES documentation on how to translate language
names. Now using django.utils.translation.ugettext_lazy instead
of a dummy gettext() function.

Thanks to Salvatore for the report.

Backport of 8bc350b385 from master.

docs/ref/settings.txt

@@ -1325,29 +1325,19 @@ This specifies which languages are available for language selection. See
 Generally, the default value should suffice. Only set this setting if you want
 to restrict language selection to a subset of the Django-provided languages.
 
-If you define a custom :setting:`LANGUAGES` setting, it's OK to mark the
-languages as translation strings (as in the default value referred to above)
--- but use a "dummy" ``gettext()`` function, not the one in
-``django.utils.translation``. You should *never* import
-``django.utils.translation`` from within your settings file, because that
-module in itself depends on the settings, and that would cause a circular
-import.
+If you define a custom :setting:`LANGUAGES` setting, you can mark the
+language names as translation strings using the
+:func:`~django.utils.translation.ugettext_lazy` function.
 
-The solution is to use a "dummy" ``gettext()`` function. Here's a sample
-settings file::
+Here's a sample settings file::
 
-    gettext = lambda s: s
+    from django.utils.translation import ugettext_lazy as _
 
     LANGUAGES = (
-        ('de', gettext('German')),
-        ('en', gettext('English')),
+        ('de', _('German')),
+        ('en', _('English')),
     )
 
-With this arrangement, ``django-admin.py makemessages`` will still find and
-mark these strings for translation, but the translation won't happen at
-runtime -- so you'll have to remember to wrap the languages in the *real*
-``gettext()`` in any code that uses :setting:`LANGUAGES` at runtime.
-
 .. setting:: LOCALE_PATHS
 
 LOCALE_PATHS