Fixed #14584 -- Documented settings.PASSWORD_RESET_TIMEOUT_DAYS. Also fixed some cross-refs in the neighborhood. Thanks to hop for the report and Adam Mckerlie for the draft patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14437 bcc190cf-cafb-0310-a4f2-bffc1f526a37