Make GeometrySurface code fully const correct

[Dr15Jones]

Changed the return value of tangentPlane to be a 'const' smart pointer.
This avoids accidently changing internals data of the surface classes.

This problem was found by the static analyzer.

[cmsbuild]

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

Make GeometrySurface code fully const correct

It involves the following packages:

Alignment/CommonAlignmentProducer
DataFormats/GeometrySurface
FastSimulation/TrajectoryManager
RecoMuon/GlobalTrackingTools
RecoParticleFlow/PFSimProducer
TrackingTools/GeomPropagators

@civanch, @diguida, @lveldere, @cvuosalo, @mdhildreth, @cmsbuild, @nclopezo, @rcastello, @cerminar, @slava77, @mmusich can you please review it and eventually sign? Thanks.
@ghellwig, @abbiendi, @Martin-Grunewald, @tlampen, @dgulhan, @venturia, @pakhotin, @mmarionncern, @battibass, @makortel, @lgray, @cerati, @trocino, @rociovilar, @GiacomoSguazzoni, @frmeier, @rovere, @VinInn, @bellan, @mmusich, @amagitte, @appeltel, @gpetruc, @matt-komm, @bachtis 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.
If you are a L2 or a release manager you can ask for tests by saying 'please test' in the first line of a comment.

[davidlange6]

please test

[ghost]

@cmsbuild please test

[cmsbuild]

The tests are being triggered in jenkins.

[cmsbuild]

+1
Tested at: c066818
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-7409/2183/summary.html

[civanch]

+1

[Dr15Jones]

@ktf this change is purely technical.

[ktf]

Bypassing. Complain if not ok.