Allows compatability with both libtorrent 1.0 and svn (1.1) rectified with construct syntax required in boost 1.55

The fix earlier was not broken with 1.0 and just worked for svn and is unrelated to OS. It was broken because libtorrent::add_torrent_params.ti was changed from an intrusive_ptr to a shared_ptr in svn. This fix automatically detects the type to maintain compatibility.