Broken inter-page links

[sudormrfbin]

Links that link to another page in the book are broken, since they seem to omit the /book/ part in a URL like https://rhai.rs/book/language/functions.html.

The following line has been copied verbatim from https://rhai.rs/book/about/features.html, click on any of the links to see a 404 page:

Tight integration with native Rust functions and types including getters/setters, methods and indexers.