Corrade/Containers/ArrayViewStlSpan.h file new in 2019.10

STL std::span compatibility for Corrade::Containers::ArrayView and Corrade::Containers::StaticArrayView.

Including this header allows you to convert Corrade::Containers::ArrayView / Corrade::Containers::StaticArrayView from and to a C++2a std::span. A separate Corrade/Containers/ArrayViewStl.h header provides compatibility with std::array and std::vector. See ArrayView STL compatibility for more information.