removed a lot obsolete code

examples/convection_diffusion.cc

examples/ellipt.cc

examples/heat.cc

examples/navier_stokes.cc

examples/stokes0.cc

examples/stokes1.cc

examples/stokes3.cc

examples/vecellipt.cc

src/amdis/Assembler.hpp

src/amdis/Assembler.inc.hpp

src/amdis/DirichletBC.hpp

src/amdis/DirichletBC.inc.hpp

src/amdis/LinearAlgebra.hpp

src/amdis/LocalAssemblerBase.hpp

src/amdis/ProblemStat.hpp

src/amdis/common/CMakeLists.txt

src/amdis/common/TypeDefs.hpp

src/amdis/linear_algebra/CMakeLists.txt

src/amdis/linear_algebra/DOFVectorInterface.hpp

src/amdis/linear_algebra/HierarchicWrapper.hpp