Run both iterative and adaptive vertices in the FS tracking

vtx_eff_panel.pdf

Changes to run both iterative and adaptive vertex algorithms in the FS tracking from the jets, including factorising out the TTVA such that we can run separate instances of the TTVA for each algorithm.

• in principle the purpose of this change is to allow the jets to still use the iterative algorithm, so some further changes will be necessary in the code to switch to use this different vertex.

This also changes the default vertex algorithm for the b-jets to be the adaptive, so that the counts will change. Hopefully, the counts for the jet and MET slices will be unaffected.