Provide support for full ndlar geometries

[krwood]

There is interest in leveraging the work done for the 2x2 simulation+calibration+reconstruction chain for ND-LAr. At the moment a [minor] missing piece to having that in hand is at the "flow" stage. It should be easy to create modules and configurations for a ND-LAr geometry by copying over the proto_nd_flow (= 2x2) codes; however, this would also be a good chance to address Issue #58 as well.