Fixed #4437: added notes to the modpython auth handler documentation about...

Fixed #4437: added notes to the modpython auth handler documentation about using the handler with Apache 2.2. Thanks to Paul Bissex for the beginnings of the patch, and Graham Dumpleton for the rest of the info.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@6309 bcc190cf-cafb-0310-a4f2-bffc1f526a37