Deny missing documentation and flesh out existing docs

[gadomski]

By adding #![deny(missing_docs)] to the Rust crate, we can help ensure that all public items are documented. We should also add examples, when appropriate, to existing docs.

Checklist

• [x] Document lib: https://github.com/geoarrow/geoarrow-rs/pull/696
• [x] Document "shallow" mods: trait_, error, datatypes, table, chuncked_array, indexed: https://github.com/geoarrow/geoarrow-rs/pull/696
• [x] Add #![deny(missing_docs)] to top level and #![allow(missing_docs)] (or warn) to "deep" mods: https://github.com/geoarrow/geoarrow-rs/pull/696
• [ ] Document scalar
• [ ] Document io
• [ ] Document geo_traits
• [ ] Document array
• [ ] Document algorithm

[kylebarron]

Is it possible to add this for sub-crates to start? E.g. not at the top-level lib.rs but inside specific modules, and then we can slowly work our way up to documenting everything?

[gadomski]

Yup, it is, or you can #![allow(missing_docs)] on a problematic module too.

[kylebarron]

All current stable crates deny missing documentation.