* Add versioned inline namespace
Add a versioned inline namespace to prevent ABI issues when linking code
using multiple library versions.
* Add namespace macros
* Encode ABI information in inline namespace
Add _diag suffix to inline namespace if JSON_DIAGNOSTICS is enabled, and
_ldvcmp suffix if JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON is enabled.
* Move ABI-affecting macros into abi_macros.hpp
* Move std_fs namespace definition into std_fs.hpp
* Remove std_fs namespace from unit test
* Format more files in tests directory
* Add unit tests
* Update documentation
* Fix GDB pretty printer
* fixup! Add namespace macros
* Derive ABI prefix from NLOHMANN_JSON_VERSION_*
* Add C++20 3-way comparison operator and fix broken comparisons
Fixes#3207.
Fixes#3409.
* Fix iterators to meet (more) std::ranges requirements
Fixes#3130.
Related discussion: #3408
* Add note about CMake standard version selection to unit tests
Document how CMake chooses which C++ standard version to use when
building tests.
* Update documentation
* CI: add legacy discarded value comparison
* Fix internal linkage errors when building a module
* Rename 'develop' folder to 'include/nlohmann'
* Rename 'src' folder to 'single_include/nlohmann'
* Use <nlohmann/*> headers in sources and tests
* Change amalgamate config file