rem: bool operator()(const std::pair<address, peer_connection*>& p) const
add: bool operator()(const detail::session_impl::connection_map::value_type& c) const
context: 		bool operator()(const std::pair<address, peer_connection*>& p) const		{			if (p.second->get_peer_id() != id) return false;			// have a special case for all zeros. We can have any number			// of peers with that id, since it's used to indicate no id.			if (std::count(id.begin(), id.end(), 0) == 20) return false;			return true;		}