Handling the Results returned by `consume()`

[wysiwys]

Hi fax maintainers,

Thanks for all your work on this crate.

In the implementation of Entry::find() in maps.rs, there are some calls to reader.consume(len) where the Result returned is not handled. Currently, this leads to some Rust compiler warnings being generated. Is the intended behavior to skip handling these Results?

If it would be helpful, I can go ahead and make a PR that makes this behavior explicit, or instead make one with some additional error handling for these cases.