Fixed #10100 -- Corrected handling of the negation required exclude() clauses...

Fixed #10100 -- Corrected handling of the negation required exclude() clauses that reference aggregate columns. Thanks to Anossov for the report.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@9785 bcc190cf-cafb-0310-a4f2-bffc1f526a37