Load a directory tree with csv files

[dkrikun]

Problem description

I have a directory tree with a (large) number of CSV files following the save convention (delimiter, columns for timestamp etc.).

1. I do not like loading them one-by-one, selecting column to be used for X-axis.
2. I have CSV files located in directories possible nested within other directories by the same name. I would like them to be shown in the PlotJuggler UI with the same hierarchy as on the filesystem

Answer these questions (or I will ignore your issue)

1. Describe your platform / Operative System and the version of PlotJuggler you are using.
   Ubuntu 20.04, PlotJuggler 3.9.1