Interpolation in clap long_about messages is unreadable

Interpolation strings in format!s of long_about are using positional strings (since Rust cannot use custom expressions in there) and it makes them completely unreadable when the number of placeholders is bigger than 3.

Find a way to mitigate that. (custom formatting crate such as: https://docs.rs/expression_format/latest/expression_format/ ?)

See: !62 (comment 208184)