[1.0.X] Changed the "write your own settings" recommendation to mention that Django

uses tuples, but not making it a recommendation. That might head off the endless
tuples vs. lists debates.

Fixed #8846.

Backport of r9146 from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.0.X@9147 bcc190cf-cafb-0310-a4f2-bffc1f526a37