Fixed #16115 -- Added ModelAdmin.save_related method to be able to do pre- or...

Fixed #16115 -- Added ModelAdmin.save_related method to be able to do pre- or post-save operations for objects related to the parent object currently displayed. Thanks, Julien Phalip.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16498 bcc190cf-cafb-0310-a4f2-bffc1f526a37