Fixed #14998 -- Made use of os.path.join to make sure this works on all...

Fixed #14998 -- Made use of os.path.join to make sure this works on all platforms. Thanks for the pointer, CarlFK.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@15128 bcc190cf-cafb-0310-a4f2-bffc1f526a37