Removed use of try catch for parameter checking

[Dr15Jones]

The use of try {} catch to determine if a parameter existed was causing
on the order of 100 exceptions to be thrown during startup. Changing the
code to use 'existsAs' avoids the problem.
In addition, the code no longer creates unnecessary std::string temporaries.

[Dr15Jones]

This fix is needed to make using catch throw in the debugger managable.

[cmsbuild]

A new Pull Request was created by @Dr15Jones (Chris Jones) for CMSSW_7_4_X.

Removed use of try catch for parameter checking

It involves the following packages:

HLTriggerOffline/Exotica

@cmsbuild, @danduggan, @nclopezo, @deguio can you please review it and eventually sign? Thanks.
@Martin-Grunewald this is something you requested to watch as well.
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@Degano you are the release manager for this.
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[deguio]

+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 or unless it breaks tests. This pull request requires discussion in the ORP meeting before it's merged. @davidlange6, @Degano, @ktf, @smuzaffar

[cmsbuild]

+1
Tested at: f25bfa2
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7651/2501/summary.html

[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 requires discussion in the ORP meeting before it's merged. @davidlange6, @Degano, @ktf, @smuzaffar

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7651/2501/summary.html

[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 requires discussion in the ORP meeting before it's merged. @davidlange6, @Degano, @ktf, @smuzaffar

[davidlange6]

+1