Add note about dashes

[lnicola]

No description provided.

[KodrAus]

Ah this is a good point! Thanks @lnicola!

This happens because what we print after the timestamp is the Rust module path to the log message. So it uses the crate name that you would use with extern crate which is always an underscore, instead of the crate name that you set in your Cargo.toml which can have dashes.

[lnicola]

@KodrAus Yup, I figured out the reason, but this took me a while to figure because the logs were working on one computer and not on another. The difference was the target (I assume release builds show less), but it was still confusing 😄.

Do you think the explanation should be mentioned in the docs?

[lnicola]

I added a note and changed "dashes" to "hyphens".

[KodrAus]

Thanks @lnicola! I'll merge this in.