- renamed options to `snake_case`
- tests, examples and cmake config now explicitly disabled when used as a subproject
- removed small_binaries (it's now implicit when building as release)
- added minimum meson version 0.53
also:
- decoupled `TOML_EXCEPTION` from ex. mode (closes#13)
- added `TOML_OPTIONAL_TYPE` customization point
- added tests for a custom optional type
- ci refactoring
also:
- fixed printing bug in operator << for source_position
- improved quality of error messages for boolean and inf/nan parsing
- documentation fixes