The issue #4 was about changelist filter always pointing to the `All`
option irrespective of the choice selected by user. The reason was that
filter rendering happens after calls to ``model_admin.queryset`` which in
turn removes the ``status`` parameter from GET dict. So being unable to
retrieve the selected ``status``, the filter always sets the lookup_val as
None. None corresponds to the choice, ``All``. Fixed the issue by extracting
the ``status`` parameter from the request path.