Refactoring: Simplify templates based on (supported) char types

[Flamefire]

Instead of explicit instantiation for each supported char type and an extra copy for documentation generation reduce to only a single template and instantiate the whole class explicitly. To ensure a reasonable error is generated introduce an is_supported_char-trait and static_assert on it. To further reduce the repetition when instantiating the templates create a macro to loop over the supported char types.

[codecov[bot]]

Codecov Report

Merging #169 (9b0e615) into develop (78d8a4e) will decrease coverage by 0.01%. The diff coverage is 100.00%.

Additional details and impacted files

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