Update L1B reader to match DLR L1B format.
The current L1B reader is not yet compatible with the final L1B format as provided by DLR. We need to update it to make it read the DLR L1B test data.
The current L1B reader is not yet compatible with the final L1B format as provided by DLR. We need to update it to make it read the DLR L1B test data.