Add discard_spikes/clean_spikes step in a curation v3 #4261
Description
Right now, the curation has:
removed: units to removemerges: unit groups to mergesplits: unit to split into 2 or multiple sub-units
One another very common use case is to "clean" units. For example, if you have a nice and clean unit with a very nasty noisy event it's easy to remove (most) of those noisy spikes. Currently, to achieve this, one would need a 2 step curation: the first one to perform the split, the second to remove the "noisy" splitted unit.
This is to propose another "step" in the curation model (and make a version 3) which does both of the steps in one go!
It should be very easy on the implementation side: the "discard_spikes" could be run as the first step, and internally perform splits whose units to remove would just be added to the removed units.