[packagekit] Attention python backend authors

[Richard Hughes]

Another trivial python API break, this time:

commit a7f3186db437e3409f8f72d7bd1c631abc63fedd
Author: Richard Hughes <richard at hughsie.com>
Date:   Wed Mar 3 14:06:28 2010 +0000

    Break internal python API by supplying a list of filters to the
backend, not a delimited list

So if you're doing

filters = filters.split(';')

....you don't need to do that anymore. Please fix up your backend in
the next month. I'll fix yum.

Thanks.

Richard.