Billy Rieger

@drahnr You should be able to remove the patched `bimap` source as `v0.6.1` includes your changes to the `serde` implementations.

Thank you for the suggestion! It might be possible to partially replicate the [`Entry`](https://doc.rust-lang.org/std/collections/hash_map/enum.Entry.html) API but anything returning a mutable reference to the inserted value would become an immutable reference...

Yes, I'd be happy to review a pull request with those changes. The iteration order is preserved for BiBTreeMap but not for BiHashMap. I can make a note of that...