Move progress handler to IComputationTerms needing it

Core/Computation/DelayedProgressCounter.cpp

Core/Computation/DelayedProgressCounter.h

Core/Computation/GISASSpecularComputationTerm.h

Core/Computation/IComputationTerm.cpp

Core/Computation/IComputationTerm.h

Core/Computation/ParticleLayoutComputation.cpp

Core/Computation/ParticleLayoutComputation.h

Core/Computation/RoughMultiLayerComputation.cpp

Core/Computation/RoughMultiLayerComputation.h