Merge branch 'remove-deprecated-std-noexcept-hh' into 'master'

[std/noexcept.hh] Remove, deprecated in 2.6.

See merge request core/dune-common!482

dune/common/std/CMakeLists.txt

 install(
   FILES
   apply.hh
-  noexcept.hh
   make_array.hh
   memory.hh
   optional.hh

dune/common/std/noexcept.hh

-#ifndef DUNE_COMMON_STD_NOEXCEPT_HH
-#define DUNE_COMMON_STD_NOEXCEPT_HH
-
-#warning The header dune/common/std/noexcept.hh is deprecated. Remove the include and use "noexcept".
-
-#define DUNE_NOEXCEPT noexcept
-
-#endif // DUNE_COMMON_STD_NOEXCEPT_HH