FastSim BugFix : PreMix : fix segfault, fix L1 reco, fix digisim link for muons, fix track validation

[lveldere]

replaces #13071, #13110

Lots of fixes in one pr, but they are all entangled

Fix L1 reco, fix seg fault in premix relvals

FastSim no longer runs
SLHCUpgradeSimulations/Configuration/postLS1CustomsPreMixing.customisePostLS1
because it overwrites modification defined in the fastsim era and the run2 eras

New EDAlias for caloStage1LegacyFormatDigis to make the l1extraParticles function properly.

Note: FullSim still runs SLHCUpgradeSimulations/Configuration/postLS1CustomsPreMixing.customisePostLS1 in the DIGI step.
At some point also FullSim should move away from this.

Fix digi-sim links for muons

FastSim now runs
SimGeneral/DataMixingModule/customiseForPremixingInput.customiseForPreMixingInput
This customisation function should not affect anything but validation and dqm,
and the customisation function was modified accordingly.
Note: FullSim had never trouble with this because there the customisation function is only applied on the RECO,VALIDATION,DQM jobs.

Fix track validation

Thanks to SimGeneral/DataMixingModule/customiseForPremixingInput.customiseForPreMixingInput, the tracking particle collection should now include PU tracks

[cmsbuild]

A new Pull Request was created by @lveldere for CMSSW_8_0_X.

It involves the following packages:

Configuration/Applications
Configuration/EventContent
Configuration/PyReleaseValidation
Configuration/StandardSequences
FastSimulation/Configuration
SimGeneral/DataMixingModule

@civanch, @lveldere, @boudoul, @franzoni, @mdhildreth, @fabozzi, @cmsbuild, @ssekmen, @srimanob, @hengne, @davidlange6 can you please review it and eventually sign? Thanks.
@ghellwig, @wmtan, @makortel, @GiacomoSguazzoni, @rovere, @VinInn, @Martin-Grunewald, @matt-komm, @cerati, @dgulhan this is something you requested to watch as well.
@slava77, @Degano, @smuzaffar you are the release manager for this.

cms-bot commands are list here #13028

[lveldere]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/10840/console

[cmsbuild]

+1
Tested at: e8f4b9c
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-13125/10840/summary.html

The following merge commits were also included on top of IB + this PR after doing git cms-merge-topic:
a2c0706
You can see more details here:
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-13125/10840/git-log-recent-commits
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-13125/10840/git-merge-result

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-13125/10840/summary.html

[mdhildreth]

+1

[fabozzi]

+1