fixed add_piece()

src/torrent.cpp

@@ -600,6 +600,8 @@ namespace libtorrent
 			picker().mark_as_downloading(block, 0, piece_picker::fast);
 			picker().mark_as_writing(block, 0);
 		}
+		async_verify_piece(piece, bind(&torrent::piece_finished
+			, shared_from_this(), piece, _1));
 		picker().dec_refcount(piece);
 	}