Re-implement addJetCollection and b-tagging setup

[sidnarayanan]

Use an implementation like @yiiyama wrote for MitProd:

https://github.com/cpausmit/MitProd/blob/7a3d608ecd0ea6425f1e673580f800d9ba3f59b0/TreeFiller/python/utils/setupBTag.py
https://github.com/cpausmit/MitProd/blob/7a3d608ecd0ea6425f1e673580f800d9ba3f59b0/TreeFiller/python/utils/makeFatJets.py

The CMSSW way of doing it seems to break every other release, including on 8_0_26_patch1. We're halfway there already with b-tagging.