Porting fig 9.6 of flato13 to version 2 in branch
https://github.com/ESMValGroup/ESMValTool/tree/version2_flato13_fig9-6
including upgrades (different projects plotted next to each other, size adjustments according to ranges, plot size adjustment with a large number of variables)

Pushed version works already, Iris problems with the EC-Earth model:
in tas - error: height2m: does not exist
in pr - error: cannot concatenate cubes