Cleanup in GUI functional tests

Core/StandardSamples/CoreFunctionalTest.cpp

Core/StandardSamples/CylindersAndPrismsBuilder.cpp

Core/StandardSamples/CylindersAndPrismsBuilder.h

Core/StandardSamples/FunctionalTestRegistry.cpp

Core/StandardSamples/SampleBuilderFactory.cpp

Core/StandardSamples/SimulationRegistry.cpp

Core/StandardSamples/StandardSimulations.cpp

Core/StandardSamples/StandardSimulations.h

Core/StandardSamples/TestFormFactorsRegistry.cpp

Examples/python/utils/plot_intensity_data.py

GUI/coregui/Models/GUIExamplesFactory.cpp

GUI/coregui/Models/GUIExamplesFactory.h

Tests/FunctionalTests/TestCore/CMakeLists.txt

Tests/FunctionalTests/TestGUI/CMakeLists.txt

Tests/FunctionalTests/TestGUI/TestGUI01/TestGUI01.cpp

Tests/FunctionalTests/TestGUI/TestGUI02/TestGUI02.cpp