NetGear Downloader: Add magnetic link and NAS support

As others have posted, please add support for magnetic links.

Likewise, though the X10 (R9000) has support for reading from NAS's (Plex, and going so far as to support Port Aggregation and SFP+), it'd make sense to be able to download to a NAS...

Thanks! 

ps: Another idea might be to support Transmition on the NIghthawks (you already support it on the ReadyNAS devices)