Migrate magnetic field tracking to refactory-2020

List of potentially affected files:

• .gitlab-ci.yml
• CMakeLists.txt
• Data
• Documentation/Examples/boundary_example.cc
• Documentation/Examples/cascade_example.cc
• Documentation/Examples/cascade_proton_example.cc
• Documentation/Examples/em_shower.cc
• Documentation/Examples/hybrid_MC.cc
• Documentation/Examples/vertical_EAS.cc
• Environment/BaseExponential.h
• Environment/CMakeLists.txt
• Environment/DensityFunction.h
• Environment/Environment.h
• Environment/FlatExponential.h
• Environment/HomogeneousMedium.h
• Environment/IEmpty.hpp
• Environment/IMediumModel.h
• Environment/InhomogeneousMedium.h
• Environment/LinearApproximationIntegrator.h
• Environment/MediumTypes.h
• Environment/NoMagneticField.h
• Environment/ShowerAxis.cc
• Environment/ShowerAxis.h
• Environment/SlidingPlanarExponential.h
• Environment/VolumeTreeNode.h
• Environment/testEnvironment.cc
• Environment/testShowerAxis.cc
• Framework/Analytics/testClassTimer.cc
• Framework/Cascade/Cascade.h
• Framework/Cascade/testCascade.cc
• Framework/Cascade/testCascade.h
• Framework/Geometry/CMakeLists.txt
• Framework/Geometry/Helix.h
• Framework/Geometry/Intersections.hpp
• Framework/Geometry/Line.h
• Framework/Geometry/Sphere.h
• Framework/Geometry/Trajectory.h
• Framework/Geometry/testGeometry.cc
• Framework/ProcessSequence/ProcessSequence.h
• Framework/Units/PhysicalUnits.h
• Framework/Utilities/CMakeLists.txt
• Framework/Utilities/quartic.cpp
• Framework/Utilities/quartic.h
• Processes/CMakeLists.txt
• Processes/CONEXSourceCut/testCONEXSourceCut.cc
• Processes/NullModel/testNullModel.cc
• Processes/ObservationPlane/ObservationPlane.cc
• Processes/ObservationPlane/ObservationPlane.h
• Processes/ObservationPlane/ObservationPlane_interpolation.cc
• Processes/ObservationPlane/testObservationPlane.cc
• Processes/ParticleCut/testParticleCut.cc
• Processes/Proposal/PROPOSAL
• Processes/Sibyll/testSibyll.cc
• Processes/StackInspector/testStackInspector.cc
• Processes/TrackWriter/TrackWriter.cc
• Processes/Tracking/CMakeLists.txt
• Processes/Tracking/Intersect.hpp
• Processes/Tracking/testTracking.cc
• Processes/TrackingLeapFrogCurved/CMakeLists.txt
• Processes/TrackingLeapFrogCurved/Tracking.h
• Processes/TrackingLeapFrogStraight/CMakeLists.txt
• Processes/TrackingLeapFrogStraight/Tracking.h
• Processes/TrackingLine/CMakeLists.txt
• Processes/TrackingLine/Tracking.cc
• Processes/TrackingLine/Tracking.h
• Processes/TrackingLine/TrackingLine.cc
• Processes/TrackingLine/TrackingLine.h
• Processes/TrackingLine/testTrackingLine.cc
• Setup/SetupEnvironment.h
• Setup/SetupTrajectory.h
• Stack/History/HistoryObservationPlane.cpp
• ThirdParty/CMakeLists.txt
• ThirdParty/cnpy/cnpy.cpp
• ThirdParty/phys/units/quantity.hpp
• Tools/plot_tracks.py
• do-copyright.py