Ctag update 8 x

[mverzett]

Rebase of #12288 into 8_0_X, passes basic testing (at least on my set-up)

[cmsbuild]

A new Pull Request was created by @mverzett (Mauro Verzetti) for CMSSW_8_0_X.

It involves the following packages:

PhysicsTools/PatAlgos
RecoBTag/CTagging

@cvuosalo, @monttj, @cmsbuild, @slava77, @vadler, @davidlange6 can you please review it and eventually sign? Thanks.
@rappoccio, @imarches, @ahinzmann, @acaudron, @mmarionncern, @jdolen, @nhanvtran, @schoef, @ferencek, @gpetruc, @mariadalfonso, @pvmulder, @TaiSakuma this is something you requested to watch as well.
@slava77, @Degano, @smuzaffar you are the release manager for this.

Following commands in first line of a comment are recognized

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• [@cmsbuild,] please test: L1/L2 and selected users to start jenkins tests
• [@cmsbuild,] please test with cms-sw/cmsdist#<PR>: L1/L2 and selected users to start jenkins tests using externals from cmsdist

[slava77]

@cmsbuild please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/9951/console

[cmsbuild]

+1
Tested at: d4cbb5b
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-12565/9951/summary.html

The following merge commits were also included on top of IB + this PR after doing git cms-merge-topic:
d4cbb5b
You can see more details here:
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-12565/9951/git-log-recent-commits
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-12565/9951/git-merge-result

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-12565/9951/summary.html

@slava77 there are some missing matrix maps:

• 1306.0_SingleMuPt1_UP15+SingleMuPt1_UP15+DIGIUP15+RECOUP15+HARVESTUP15

[cvuosalo]

+1

For #12565 d4cbb5b

Add c tagging discriminators.

The code change is satisfactory, and Jenkins tests against baseline CMSSW_8_0_X_2015-11-24-2300 show no significant differences.