Merge branch 'feature/shut-up-compiler-warnings' into 'master'

dune/geometry/axisalignedcubegeometry.hh

dune/geometry/multilineargeometry.hh

dune/geometry/quadraturerules.hh

dune/geometry/quadraturerules/jacobiNquadrature.hh

dune/geometry/quadraturerules/prismquadrature.hh

dune/geometry/referenceelementimplementation.hh

dune/geometry/test/test-affinegeometry.cc

dune/geometry/test/test-axisalignedcubegeometry.cc

dune/geometry/test/test-constexpr-geometrytype.cc

dune/geometry/test/test-geometrytype-id.cc

dune/geometry/test/test-multilineargeometry.cc

dune/geometry/test/test-nonetype.cc

dune/geometry/test/test-refinement.cc

dune/geometry/type.hh