flatter directory strucure for Python examples

Examples/Python/README.md

Examples/Python/fit51_Basic/README.md

Examples/Python/fit51_Basic/basic_fitting_tutorial.py

...les/Python/fit51_Basic/basic_fitting_tutorial_data.txt.gz

Examples/Python/fit51_Basic/consecutive_fitting.py

Examples/Python/fit51_Basic/minimal_fit_example.py

Examples/Python/fit51_Basic/minimizer_settings.py

Examples/Python/fit52_Advanced/README.md

Examples/Python/fit52_Advanced/find_background.py

Examples/Python/fit52_Advanced/fit_along_slices.py

Examples/Python/fit52_Advanced/fit_with_masks.py

Examples/Python/fit52_Advanced/multiple_datasets.py

...Python/fit53_CustomObjective/custom_objective_function.py

Examples/Python/fit54_ExternalMinimizer/lmfit_basics.py

...les/Python/fit54_ExternalMinimizer/lmfit_with_plotting.py

Examples/Python/fit55_Specular/FitSpecularBasics.py

Examples/Python/fit55_Specular/FitWithUncertainties.py

Examples/Python/fit55_Specular/README.md

...les/Python/fit55_Specular/RealLifeReflectometryFitting.py

...es/Python/fit55_Specular/genx_interchanging_layers.dat.gz