IVF in the RECO sequence + trackJetPt as taggingvariable

1) placeholder for track-based jet pt in TaggingVariable 
- announced: 
	- https://twiki.cern.ch/twiki/bin/viewauth/CMS/CMSSW_7_1_0
	- https://twiki.cern.ch/twiki/bin/viewauth/CMS/BTagSoftware#Revise_the_jet_pT_definition_for
- discussed in various BTV meetings:
	- slide 4 of https://indico.cern.ch/event/300388/session/0/contribution/0/material/slides/0.pdf
	- slide 14 of https://indico.cern.ch/event/302907/contribution/3/material/slides/0.pdf
	- slide 5 of https://indico.cern.ch/event/303434/session/0/contribution/0/material/slides/0.pdf

2) IVF in the RECO sequence 
- announced here https://twiki.cern.ch/twiki/bin/viewauth/CMS/CMSSW_7_1_0
- discussed in meetings:
	- slide 5 of https://indico.cern.ch/event/303434/session/0/contribution/0/material/slides/0.pdf
	- https://indico.cern.ch/event/307998/