fix beamspot for wf for minbias pu events

[lveldere]

I edited the FastSim wf for minbias events to be used as pileup input.

I changed the beamspot from 'Realistic8TeVCollision' to the more appropriate 'NominalCollision2015',
and while on it removed a couple of obsolete lines.

[cmsbuild]

A new Pull Request was created by @lveldere for CMSSW_7_4_X.

fix beamspot for wf for minbias pu events

It involves the following packages:

Configuration/PyReleaseValidation

@cmsbuild, @srimanob, @nclopezo, @boudoul, @franzoni can you please review it and eventually sign? Thanks.
@ghellwig, @Martin-Grunewald this is something you requested to watch as well.
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[ghost]

@cmsbuild please test

[cmsbuild]

The tests are being triggered in jenkins.

[cmsbuild]

+1
Tested at: 744012c
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7460/2243/summary.html

[cmsbuild]

+1
Tested at: 744012c
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7460/2249/summary.html

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7460/2243/summary.html

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7460/2249/summary.html

[franzoni]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_7_4_X IBs unless changes (tests are also fine). This pull request will be automatically merged.