static data member is not thread safe and doesn't need to be static

[wmtan]

The class SmartPropagator has a non-const static data member that should not be static, for several reasons:

1. it's not thread safe.
2. If the constructor gets called multiple times with different values of the 'epsilon' argument, the new value will not be used. This is a bug. In CMSSW at the moment, it is always called with the same value, but it still is a bug.

This pull request makes the data member non-static.

[cmsbuild]

A new Pull Request was created by @wmtan for CMSSW_7_0_X.

static data member is not thread safe and doesn't need to be static

It involves the following packages:

TrackingTools/GeomPropagators

@nclopezo, @cmsbuild, @thspeer, @slava77 can you please review it and eventually sign? Thanks.
@gpetruc, @cerati, @GiacomoSguazzoni, @rovere this is something you requested to watch as well.
You can sign-off by replying to this message having '+1' in the first line of your reply.
You can reject by replying to this message having '-1' in the first line of your reply.
@ktf you are the release manager for this.

[cmsbuild]

+1
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/1251/summary.html

[thspeer]

+1
Tested 48829b3 in CMSSW_7_0_X_2013-11-08-0200-1374
No difference in reco, based on RelMon and reco scripts.

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next IBs unless changes or unless it breaks tests. @ktf can you please take care of it?