Simplify boolean expressions.

Applications/DataExplorer/Base/OGSError.cpp

Applications/DataExplorer/VtkVis/VtkStationSource.cpp

Applications/FileIO/TetGenInterface.cpp

Applications/Utils/FileConverter/ConvertSHPToGLI.cpp

GeoLib/AnalyticalGeometry.cpp

GeoLib/IO/Legacy/OGSIOVer4.cpp

GeoLib/IO/XmlIO/Qt/XmlStnInterface.cpp

GeoLib/Polygon.cpp

GeoLib/Polyline.cpp

GeoLib/Raster.cpp

GeoLib/Triangle.cpp

MathLib/GeometricBasics.cpp

MeshLib/Properties.cpp

...ib/ODESolver/ConvergenceCriterionPerComponentResidual.cpp

Tests/GeoLib/TestLineSegmentIntersect2d.cpp