TRestAnalysisPlot feature allowing to plot accumulative map observables inside a TRestAnalysisTree

[jgalan]

This feature would allow to create for example a channel activity weighted with different detector parameters.

I.e. if we have the risetime value versus the channel ID at our analysisTree, then it would be interesting to show the average rise time per channel in a single plot, either average or accumulated total.

We could produce an activity channel weighted with the energy using the map variable holding the pulse amplitude versus channel ID.

And so on. We are not able yet to do this kind of plots directly with TRestAnalysisPlot.