Changing the vertex matching algorithm for taus

Redesign of vertex-to-jet matching algorithm used by tauReco. The only functional change is the possibility to select which way the jet leading PFcandidate will be selected. Also, the default matching was changed from using track weights to using deltaZ.

The performance is slightly affected in a positive way - increased efficiency and decreased fake rate

The change in performance is documented here: https://indico.cern.ch/event/316898/material/1/0.pdf

This pull request contains the fix for memory leak from #3666 and does not interfere with ak5->ak4 transition

@monicava, @veelken - you want to watch this