[1.2.X] Fixed #14840 -- Added crossrefs to related objects reference docs....

[1.2.X] Fixed #14840 -- Added crossrefs to related objects reference docs. Thanks to adamv for the report and patch.

Backport of [14842] from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.2.X@14843 bcc190cf-cafb-0310-a4f2-bffc1f526a37