lowercase in material_vacuum etc

Examples/scatter2d/ApproximationDA.py

Examples/scatter2d/ApproximationLMA.py

Examples/scatter2d/ApproximationSSCA.py

Examples/scatter2d/BiMaterialCylinders.py

Examples/scatter2d/BoxesWithSpecularPeak.py

Examples/scatter2d/CosineRipplesAtRectLattice.py

Examples/scatter2d/CylindersAndPrisms.py

Examples/scatter2d/CylindersInBA.py

Examples/scatter2d/HalfSpheresInAverageTopLayer.py

Examples/scatter2d/HexagonalLatticesWithBasis.py

Examples/scatter2d/Interference1DLattice.py

Examples/scatter2d/Interference1DRadialParacrystal.py

Examples/scatter2d/Interference2DCenteredSquareLattice.py

Examples/scatter2d/Interference2DParacrystal.py

Examples/scatter2d/Interference2DRotatedSquareLattice.py

Examples/scatter2d/Interference2DSquareFiniteLattice.py

Examples/scatter2d/MagneticSpheres.py

Examples/scatter2d/Mesocrystal.py

Examples/scatter2d/Mesocrystal2.py

Examples/scatter2d/Mesocrystal3.py