Add PFlow constituents to FTAG1
This MR adds the flow elements for PFlow and UFO jets. Based on https://its.cern.ch/jira/browse/AFT-619, track thinning was not added.
A test sample is available here:
/afs/cern.ch/user/l/ligang/public/FTag_R22/ftag1_jet_const5/
See also: https://its.cern.ch/jira/browse/AFT-609
Edited by Samuel Van Stroud