Prepare for v4.25 release (#89)

Remove spurious variables that shouldn't have been added

Create release 4.23 (#80)

* Prepare for release v4.23
* Add installation, building, and testing instructions to README
* Update Makefile to use C++17 for GoogleTest 1.17.0 compatibility

Co-authored-by: Claude <noreply@anthropic.com>

Prepare for release v4.22 (#73)

* Update CMakeLists.txt

* Update release.txt

* Update SimpleIni.h

Prepare for new release with recent changes

Prepare for 4.20 release

Release 4.19

Release 4.18

Prepare for release