Add copperplate post precessing step

[staadecker]

Add a post processing step that when enabled moves all the projects to the same load zone and removes the transmission module. This is a "copperplate" model and is useful to compare to copperplate models used in other studies. We may want a way to remove duplicate candidate generation plants so that if previously there were 50 plants of the same type (one in each load zone) we are only left with one plant in our copperplate model (with a 50x greater limit).