Correcting typos and adding new features

[eduardburelo]

New feature: B mixing configuration option added (0: coherent, 1: incoherent), default is 1.
New feature: New models for evtgen can now be provided by users and must be placed under EvtGenUserModels directory. These new models are compiled and added to evtgen by the interface.

[cmsbuild]

A new Pull Request was created by @eduardburelo (Eduard Burelo) for CMSSW_7_4_X.

Correcting typos and adding new features

It involves the following packages:

GeneratorInterface/EvtGenInterface

@vciulli, @covarell, @thuer, @cmsbuild, @nclopezo, @bendavid can you please review it and eventually sign? Thanks.
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[bendavid]

+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.

[cmsbuild]

+1
Tested at: ffde0ae
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7208/1928/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 will be automatically merged.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7208/1928/summary.html