This release of optional lite contains the following changes:
Additions:
- Add non-standard value_or_eval() (#67).
 - Add 
[[nodiscard]]to relational operators. - Add GitHub Actions CI and badge for it (nonstd-lite-project issue 55).
 
Changes:
- Update actions/checkout in GitHub Actions to v4 (#78, thanks @striezel).
 - Update actions/checkout in GitHub Actions to v3 (#71, thanks @striezel).
 - Add/update example/CMakeLists.txt (nonstd-lite-project issue 56).
 - Remove gcc 8 and clang 8, 9, 10 from GitHub CI matrix (nonstd-lite-projet issue 69).
 - Add common CMake generated files to gitignore (#75, thanks @kacf).
 - Remove Travis CI configuration and badge (#73, thanks @striezel).
 - Remove msvc (windows-2016) image from GitHub Actions (nonstd-lite-project issue 61, thanks @xavier2k6).
 - Add msvc (windows-2022) image to GitHub Actions (nonstd-lite-project issue 62).
 - Do not cancel all jobs in a workflow if one fails. (#72, thanks @striezel, nonstd-lite-projet issue 71).
 - Use toplevel unit_name (nonstd-lite-project 56).
 - Update CMakeLists.txt for examples (nonstd-lite-project 56).
 - Change value used with *_CPP20_OR_GREATER to 202002L (nonstd-lite-project issue 49) Now, designate C++23 as speculative.
 - Prevent undefined 
_HAS_EXCEPTIONSwarning with Clang (#68, thanks @redbaron). - Use ternary operator and C++11 constexpr.
 - Use 
optional_constexpr14withvalue_or_eval()(#67). - Accommodate VS2013/MSVC12.0/1800 and earlier.
 - Update Readme guided by markdownlint.
 - In Readme, update test specification, add folding (#67).
 - In Readme, correct URLs for reference [10] Generic: Discriminated Unions.
 - In Readme, add Daniela Engert's Boost20.optional to section Other implementations of optional.
 
Fixes:
- Fix to use forwarding reference (thanks @matthew-wozniczka, fixes #74).
 - Fix some typos (#70, thanks @striezel).
 - Fix construction, emplace from const types (#69, thanks @atorstling).
 - Fix cmake config file to use @package_nspace@ (nonstd-lite issue 68).