I see them fulfilling two roles
- A form of bolding
- As a callback to their placeholder in usage
However, it is a bit of an unpolished look and no other CLI seems to do
it. This looks a bit more proefessional. We have colored help for
formatting and I think the sections relation to usage will be clear
enough.
Instead of just renaming it, I reconsidered what the API should look
like. A custom separator for author does not make sense positionally
but accepting a name, and defaulting it, does fit with what someone
would expect.
I removed the `_from_crate` suffix because it doesn't seem necessary.
We don't have this kind of naming for the derive. I feel it cleans
things up this way.