Merge branch 'feature/restructure_mpl' into 'develop'

src/amdis/ProblemStat.inc.hpp

src/amdis/ProblemStatTraits.hpp

src/amdis/common/Apply.hpp

src/amdis/common/CMakeLists.txt

src/amdis/common/Concepts.hpp

src/amdis/common/ForEach.hpp

src/amdis/common/Index.hpp

src/amdis/common/Logical.hpp

src/amdis/common/Loops.hpp

src/amdis/common/MultiTypeMatrix.hpp

src/amdis/common/MultiTypeVector.hpp

src/amdis/common/Range.hpp

src/amdis/common/StaticSize.hpp

src/amdis/common/TypeTraits.hpp

src/amdis/gridfunctions/FunctorGridFunction.hpp

src/amdis/gridfunctions/GridFunctionConcepts.hpp

src/amdis/linearalgebra/eigen/Constraints.hpp

src/amdis/localoperators/ConvectionDiffusionOperator.hpp

src/amdis/operations/Basic.hpp

src/amdis/operations/Composer.hpp