Packets with no payload that are marked as scrambled should not be dropped.

TsWriter currently ignores all packets marked as scrambled. Usually this is correct behaviour. However, in the case of a packet with an adaption field and no payload, the adaption field is never actually scrambled... I think.

Technically, these packets should be marked as not scrambled by the CAM, however it appears some CAMs (the Unicam) and/or some tuner drivers (DD Cine) do not cause this to happen.

TsWriter should ignore the scrambled bits and *not* drop no-payload packets.

This is critical in the case where the PCR is exclusively carried in packets where there is no payload.