duplicate torrent or not duplicate

Hi Maybe it's finally time to return the result, duplicated torrent or not duplicated from torrent.py? In [this](https://github.com/trim21/transmission-rpc/blob/6bc74cc3c89e2a491c55f619b2fd8d67dc20b39a/transmission_rpc/client.py#L338) Something like that ``` item = data['arguments']['torrent-duplicate'] item['duplicate'] = 1 ```