Add TrackingParticle selector (fix for #4132)

[mark-grimes]

This is a fix for #4132 (EDIT - I meant #3142) which adds an extra parameter. stableOnlyTP should be true for FastSim and false for FullSim, so I set it to false. I don't actually know how FastSim is configured though.

[cmsbuild]

A new Pull Request was created by @mark-grimes (Mark Grimes) for CMSSW_6_2_X_SLHC.

Add TrackingParticle selector (fix for #4132)

It involves the following packages:

SimGeneral/MixingModule

@cmsbuild, @civanch, @Degano, @mdhildreth, @nclopezo can you please review it and eventually sign? Thanks.
@wmtan this is something you requested to watch as well.
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@andersonjacob, @mark-grimes you are the release manager for this.
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[mark-grimes]

merge

Tests 10000, 10200, 10400, 11200, 11400 and 12000 all pass. I have more running but I'm confident they will be okay too.