Doxy class and file comments: unify wording "abstract base class" or

Base/Pixel/IPixel.h

Core/Scan/ISpecularScan.h

Core/Simulation/ISimulation.h

Core/Simulation/ISimulation2D.h

Core/Term/SpecularComputationTerm.h

Fit/Minimizer/IMinimizer.h

Fit/RootAdapter/RootMinimizerAdapter.h

Param/Base/IParameter.h

Sample/Aggregate/IInterferenceFunction.h

Sample/Correlations/IPeakShape.h

Sample/FFCompute/IComputeFF.h

Sample/Lattice/ISelectionRule.h

Sample/Particle/IParticle.h

Sample/SampleBuilderEngine/ISampleBuilder.cpp

Sample/SampleBuilderEngine/ISampleBuilder.h

Sample/Scattering/IBornFF.h

Sample/Scattering/IFormFactor.h

Sample/Scattering/IFormFactorDecorator.h

Sample/Scattering/ISample.h

Sample/Scattering/Rotations.h