Export the 'card' properties of sources and sinks into the Python layer.
Export the 'card' properties of sources and sinks into the Python layer.

Signed-off-by: Bert Wesarg <0d62a3713d750bb3a7440aad892eb1fd24c11fa3@googlemail.com>

mk-fg/python-pulse-control,mk-fg/python-pulse-control