Multitude of plugins, when saving intermediate plugins?

Created by: jorana

Like #174 (closed) there are downsides of having a lot of plugins for processing (all of our) sub-detectors. Due to e.g. high energy #161, neutron veto #86 and muon veto #173 plugins there are trade-offs between having a lot of small steps in between the plugins (like e.g. peaklets -> peaks) and saving all of those and the computational effort to keep all of that data stored somewhere.

We may need to - at some point - carefully think about which datatypes we want to store/compute. As a starters some plugins could be better of not being saved e.g. by setting https://github.com/AxFoundation/strax/blob/master/strax/plugin.py#L24 or by merging it with another plugin.