cubicweb-brainomics #3280268 Split populate scripts [open]

We should split the Brainomics importer in different populate scripts in each cube.

The Brainomics cube should only create the links (e.g. assessments) between the different generated data.

prioritynormal
typebug
done in<not specified>
load3.000
load left3.000
closed by<not specified>