* deprecated features adopted into C++
1) Mark the following GSL features as deprecated:
- gsl::unique_ptr (always)
- gsl::shared_ptr (always)
- gsl::byte (since c++17)
- gsl::joining_thread (never implemented)
2) Refactor existing deprecations to use the new GSL_DEPRECATED(msg) macro.
3) Create a section in the README for deprecated features in the
standard.
* do not deprecate gsl::to_integer because we never claim to implement it.
* do not use gsl::byte if it is deprecated
Reverts commit that changes #include "assert" -> #include "gsl/assert".
This change is necessary in order to comply with CppCoreGuideline's
SF.12. Now we do #include "./assert".
Office is seeing build breaks due to `#include "span"` including
C++20 span instead of gsl/span. Most likely we want all headers
includes qualified with "gsl/" to avoid similar issues.
* move span specialization of 'at' to <gsl/span> and update the parameter to be taken by reference
* undid previous changes and acted upon decisions made in maintainer sync. Fixed tests failing in /kernel mode
* ran clang-format on the include folder
* ran clang-format on the test folder
Co-authored-by: Jordan Maples <jordan.maples@microsoft.com>
