Work on pdd and some other small code refactorings.

AMDiS/libtool

AMDiS/src/AMDiS.h

AMDiS/src/DOFAdmin.h

AMDiS/src/DOFMatrix.cc

AMDiS/src/ParallelDomainProblem.cc

AMDiS/src/ParallelDomainProblem.h

AMDiS/src/SurfaceOperator.h

AMDiS/src/SurfaceQuadrature.cc

AMDiS/src/SurfaceQuadrature.h

AMDiS/src/SurfaceRegion_ED.h

AMDiS/src/SystemVector.h

AMDiS/src/TecPlotWriter.h

AMDiS/src/Tetrahedron.h

AMDiS/src/TimedObject.h

AMDiS/src/Traverse.h

AMDiS/src/TraverseParallel.h

AMDiS/src/Triangle.h