plot_tracks.sh need two data files as parameters

Hi all:

I am trying to install CORSIKA and run the share/examples/cascade_example as indicated in README.md. I have now successfully installed CORSIKA in my docker container and run share/examples/cascade_example and generated track_dat file. But I found that the share/tools/plot_tracks.sh took two data files track_dat and muon_dat rather than a single track_dat since commit 8ffc9580.

I want to know what the muon_dat stands for and how can I generate this file. And maybe we should update the README.md file to adapt new changes

Thanks

Fan