[1.0.X] Fixed #9514 -- Made admin change_form template correctly...

[1.0.X] Fixed #9514 -- Made admin change_form template correctly recognize/report when a form has only a single error. 

[9371] from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.0.X@9372 bcc190cf-cafb-0310-a4f2-bffc1f526a37