Allow for no_graph option in plot_shock_decomposition
It would be useful for me to allow the option no_graph to plot_shock_decomposition. It seems a bit silly, but one may be just interested in the xls output without the fig one.
The option would trigger
options_.no_graph.plot_shock_decomposition=1
while by default it will be
options_.no_graph.plot_shock_decomposition=0
in global_initialization