Unify parameter names Length, Radius -> BaseEdge

Core/FormFactors/FormFactorCone6.h

Core/FormFactors/FormFactorPolyhedron.h

Core/FormFactors/FormFactorPrism3.cpp

Core/FormFactors/FormFactorPrism3.h

Core/FormFactors/FormFactorPrism6.cpp

Core/FormFactors/FormFactorPrism6.h

Core/FormFactors/FormFactorPyramid.cpp

Core/FormFactors/FormFactorPyramid.h

Core/FormFactors/FormFactorTetrahedron.cpp

Core/FormFactors/FormFactorTetrahedron.h

Core/PythonAPI/libBornAgainCore.py

Core/PythonAPI/libBornAgainCore_wrap.cxx

Core/Tools/PyGenVisitor.cpp

GUI/coregui/Models/FormFactorItems.cpp

GUI/coregui/Models/FormFactorItems.h

GUI/coregui/Models/GUIObjectBuilder.cpp

Tests/UnitTests/TestCore/FormFactorTest.h

dev-tools/ad-hoc/JWu/bornplot2.py

dev-tools/ad-hoc/JWu/par_changed.py