Include total file size in addition to total data size in exdf-du

I noticed that after reduction the overhead can be on the order of 5-8%, so it seems prudent to visualize it:

(extra) schmidtp@max-exfl461:exdf-tools% exdf-du p2857:r200:red
                                                  size   ratio
total file size                                  25 GB  108.3%
total data size                                23.1 GB  100.0%
SQS_DIGITIZER_UTC1/ADC/1:network               15.7 GB   68.0%
SQS_DIAG2_LIC/CAM/YAG_DOWNSTR:daqOutput        1.34 GB    5.8%
SA3_XTD10_PES/ADC/1:network                    1.31 GB    5.7%
...