Modernising the code, improving images

src/Cxx.md

src/Cxx/Deprecated/Visualization/ShadowsOpenGL.cxx

src/Cxx/Visualization/CMakeLists.txt

src/Cxx/Visualization/DisplayQuadricSurfaces.cxx

src/Cxx/Visualization/QuadraticSurface.cxx

src/Cxx/Visualization/QuadricLODActor.cxx

src/Cxx/Visualization/QuadricVisualization.cxx

src/Cxx/Visualization/RandomProbe.cxx

src/Cxx/Visualization/RenderLargeImage.cxx

src/Cxx/Visualization/ReverseAccess.cxx

src/Cxx/Visualization/RotateActor.cxx

src/Cxx/Visualization/ScalarBarActor.cxx

src/Cxx/Visualization/ScalarBarActorColorSeries.cxx

src/Cxx/Visualization/ScalarVisibility.cxx

src/Cxx/Visualization/ScaleGlyphs.cxx

src/Cxx/Visualization/SceneBounds.cxx

src/Cxx/Visualization/SelectWindowRegion.cxx

src/Cxx/Visualization/ShadowsLightsDemo.cxx

src/Cxx/Visualization/ShepardInterpolation.cxx

src/Cxx/Visualization/SideBySideViewports.cxx