PJ4 compatibility

[SgtVoro]

PlotJuggler4 is on the horizon but unfortunately it seems like plugins made for older versions can't simply be added to PJ4.
APbin plugin would likely need some adjustments to keep this rather neat functionality going with the new PJ version.

[Georacer]

Yes, figures. Let's wait for PJ4 to release a stable version, and then we'll look at what it takes.

It will probably come down do whether the LLM gods smile upon us: I don't have a lot of time to dedicate to this repository.