fix analysis_data.channel_mean()

[sofia-calgaro]

No description provided.

[sofia-calgaro]

We don't want to calculate the mean when we deal with given parameters that are like Vectors of Vectors (eg waveforms, energy in PE, ...). These parameters can belong to whatever subsystem (geds, pulser, spms), so we have to look at their type. This is not very trivial because self.paramters is itself a list of parameters, so in principle one should need to loop over every single parameter.

A basic workaround is there at the moment, that skips only spms, independently from the inspected parameter.
This means that if we are going to load waveforms from raw tiers for geds, the code will potentially crash. However, loading waveform is not our purpose, so we might be already happy with this version