Add VSI-setup python fragment to allow easier re-running of VrtSecInclusive in derivation step
This MR creates a new python fragment in VrtSecInclusive which can be included in the derivation step to re-run secondary vertexing. Previously, the VSI setup was included in SUSY15.py, but now that it is external, it can easily be used by other derivations as well.
In the process of implementing this, we realized that several of the VSI attributes which were being set in the previous configuration were incorrectly named. This did not cause a warning/error, because python allows for the addition of new properties dynamically. With incorrect names in the VSI config, these properties were instead being set to their default values as defined in VrtSecInclusive/src/Utilities.cxx instead of what was intended by the config. We have therefore changed all VSI configs to have proper attribute names, and set these attributes to their default values, so that the outcome of the vertexing will not be impacted by these changes.