Add dependencies locally

deps/GSL/include/gsl/string_span

@@ -1,58 +1,4 @@
-///////////////////////////////////////////////////////////////////////////////
-//
-// Copyright (c) 2015 Microsoft Corporation. All rights reserved.
-//
-// This code is licensed under the MIT License (MIT).
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-//
-///////////////////////////////////////////////////////////////////////////////
-
-#ifndef GSL_STRING_SPAN_H
-#define GSL_STRING_SPAN_H
-
-#include "span_ext" // for dynamic_extent
-
-#include <cstddef>   // for size_t, nullptr_t
-
-namespace gsl
-{
-//
-// czstring and wzstring
-//
-// These are "tag" typedefs for C-style strings (i.e. null-terminated character arrays)
-// that allow static analysis to help find bugs.
-//
-// There are no additional features/semantics that we can find a way to add inside the
-// type system for these types that will not either incur significant runtime costs or
-// (sometimes needlessly) break existing programs when introduced.
-//
-
-template <typename CharT, std::size_t Extent = dynamic_extent>
-using basic_zstring = CharT*;
-
-using czstring = basic_zstring<const char, dynamic_extent>;
-
-using cwzstring = basic_zstring<const wchar_t, dynamic_extent>;
-
-using cu16zstring = basic_zstring<const char16_t, dynamic_extent>;
-
-using cu32zstring = basic_zstring<const char32_t, dynamic_extent>;
-
-using zstring = basic_zstring<char, dynamic_extent>;
-
-using wzstring = basic_zstring<wchar_t, dynamic_extent>;
-
-using u16zstring = basic_zstring<char16_t, dynamic_extent>;
-
-using u32zstring = basic_zstring<char32_t, dynamic_extent>;
-
-} // namespace gsl
-
-#endif // GSL_STRING_SPAN_H
+#pragma once
+#pragma message(                                                                                   \
+    "This header will soon be removed. Use <gsl/zstring> instead of <gsl/string_span>")
+#include "zstring"