[1.0.X] Fixed #9956: relax the URL pattern for primary keys in the comment...

[1.0.X] Fixed #9956: relax the URL pattern for primary keys in the comment redirect so that models with custom PKs aren't cut out of the loop. Backport of r10422 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.0.X@10423 bcc190cf-cafb-0310-a4f2-bffc1f526a37