Doxygen: further group comments in Tools

Core/Tools/inc/AxisBin.h

Core/Tools/inc/AxisDouble.h

Core/Tools/inc/Bin.h

Core/Tools/inc/Convolve.h

Core/Tools/inc/FastVector.h

Core/Tools/inc/FileSystem.h

Core/Tools/inc/IAxis.h

Core/Tools/inc/IChangeable.h

Core/Tools/inc/ICloneable.h

Core/Tools/inc/IFactory.h

Core/Tools/inc/INamed.h

Core/Tools/inc/IObserver.h

Core/Tools/inc/IParameterized.h

Core/Tools/inc/ISingleton.h

Core/Tools/inc/IStochasticParameter.h