New ObjectiveFunction on board of FitKernel

Fit/Kernel/FitKernel.cpp

Fit/Kernel/FitKernel.h

Fit/Kernel/FitKernelImp.cpp

Fit/Kernel/FitKernelImp.h

Fit/Kernel/IMinimizer.h

Fit/Kernel/KernelTypes.h

Fit/Kernel/ObjectiveFunction.cpp

Fit/Kernel/ObjectiveFunction.h

Fit/RootAdapter/RootMinimizerAdapter.cpp

Fit/RootAdapter/RootMinimizerAdapter.h

Fit/RootAdapter/RootObjectiveFuncAdapter.cpp

Fit/RootAdapter/RootObjectiveFuncAdapter.h

Tests/Functional/Fit/ObjectiveTestFunctions.cpp

Tests/Functional/Fit/ObjectiveTestFunctions.h

Tests/Functional/Fit/StandaloneFitTest.cpp

auto/Wrap/libBornAgainFit.py

auto/Wrap/libBornAgainFit_wrap.cpp