[1.0.X] Fixed #10694: correctly check permissions in the change password...

[1.0.X] Fixed #10694: correctly check permissions in the change password admin. Thanks, jturnbull. Backport of r10591 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.0.X@10592 bcc190cf-cafb-0310-a4f2-bffc1f526a37