cubicweb-brainomics #2950798 Add visualization tools [open]

It could be interesting to add some visualization tools in order to plot histogram/line/chart and some basic statistical test (e.g. ftest) on rset (e.g. scores/questions/basic values of generic test run).

This may be done by creating a cube based on the two following projects:

• hg@hg.logilab.org/users/vmichel/cubes/visualization
• hg@hg.logilab.org/users/vmichel/cubes/datamining