Since libtorrent 16.x, it uses 1 proxy setting for Peer,Tracker,Web Seed, and DHT. With this in mind DHT uses UDP(Not TCP). As far as i know Socks 5 is the only type that supports UDP. So the idea is to not enable DHT when a unsupported proxy is in use. Maybe want to handle this differently give the user an option but something like this would probably be nice. Perhaps maybe just a warning.

Thanks for the other commits.