TitleCase must keep separtors

[corebreaker]

The string "hello-world everyone" converted to title case should be converted to "Hello-World Everyone" according to https://titlecaseconverter.com/

Playback

[jplatte]

From the readme:

Characters not within words (such as spaces, punctuations, and underscores) are not included in the output string except as they are a part of the case being converted to.

This library is a little bit opinionated (dropping punctuation, for example). If that doesn't fit your use case, I hope there is another crate that does.