- release notes and versions

   Markus in release   ----------------- v00-12 -------

Implement cellDimensions Functions for PolarGridRPhi and PolarGridRPhi2
Implement unit tests
Correct documentation string in CartesianGrid[XY]Z

Needed to access cell dimensions in a segmentation agnostic way
Implemented unit tests for cellDimensions
Implemented default function throwing exception
Implemented cellDimensions for CartesianGridXY, XZ, YZ, XZY
Added c++11 definition to DD4hep.cmake (implemented functions with and without c++11)

 Added one 'Geant4ScintillatorCalorimeterAction' into DDG4 plugins Geant4SDActions for  scintillator to take Geant4 BirksLaw effect as sensitive detector active layer.

  Overload function 'Geant4HitData::extractContribution' with 'bool ApplyBirksLaw' for extracting the MC contribution for a given hit from the step information with BirksLaw effect option. 

 Added a switch for BirksLaw. For backward compatable, by default, do not apply BirksLaw, and apply BirksLaw with call 'doApplyBirksLaw()'.