Stand alone muon reconstruction cleaning for 72x

First step into the track to cure the "close-by muons" inefficiency.
For details see:
https://indico.cern.ch/event/331640/contribution/4/material/slides/0.pdf
Originally based on: HuguesBrun/cleanningBySegIn720
Target is 720pre3
General comment: use ++X instead of X++ (not only here).