add preliminary sense_minmax support

        self.channels = list(map(DLogChannel, channels))

        self.interval = float(dlog.find("frame").find("tint").text)

        self.sense_minmax = int(dlog.find("frame").find("sense_minmax").text)

        self.planned_duration = int(dlog.find("frame").find("time").text)

        self.observed_duration = self.interval * int(len(raw_data) / (4 * num_channels))

        if self.sense_minmax:

            raise RuntimeError(

                "DLog files with 'Log Min/Max' enabled are not supported yet"

            )

            # there's a min, current, and max reading for each channel.

            num_channels *= 3

        self.planned_duration = int(dlog.find("frame").find("time").text)

        self.observed_duration = self.interval * int(len(raw_data) / (4 * num_channels))

        self.timestamps = np.linspace(

            0, self.observed_duration, num=int(len(raw_data) / (4 * num_channels))

        self.slots = [dict(), dict(), dict(), dict()]

        for i, channel in enumerate(self.channels):

            if self.sense_minmax:

                # [i*3] == current/avg(?), [i*3 + 1] == min, [i*3 + 2] == max

                channel.data = self.data[i * 3]

            else:

                channel.data = self.data[i]

            self.slots[channel.slot - 1][channel.unit] = channel