Update and test with some newer compilers and cmake versions
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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
* Add a dedicated version option to CLI11 to facilitate use of version flags, similar to help flags
* add some test for the version flag
* update errors and formatting
* clear up gcc 4.8 warnings
* add a few more tests
* fix compiler error
* fix a few comments, and change default version flag to only use "--version"
* remove `version` calls and tests
* formatting and add `std::string version()` back in.
* Add whitespace/comments check
* Adapt spacing in clang-format
* Fix cpplint whitespace/comments issues
* Grammar
* Do not use clang-format for comment spacing
* Fix with clang-format pre-commit hook
* work on the flags book chapter and making sure the values are initialized properly.
* Fix initialization of values used in flags or options
* update some formatting and more brace initialization
* update more formatting and fix a incorrect initializer
* more formatting and some error fixes
* more formatting
* Small formatting fix
Co-authored-by: Henry Schreiner <HenrySchreinerIII@gmail.com>
