DHT, UPnP, NAT-PMP and LSD support.

DHT seems to work, however I have no way to see if the others do, so this will require testing.

Note that this also deprecates most of the Torrent methods, you'll be warned by your compiler when trying to compile deprecated code. Torrent now derives from torrent_handle, you are required to make an explicit cast on libtorrent methods that aren't taking a const torrent_handle as a parameter.
Use the torrent class without using getHandle() from now.