- Change the return type of metadata convenience iter functions to
actual iterators instead of allocated collections
- The iterator item type is set to be a reference
- `from_repeated_message` -> `impl_from_repeated`
- `from_repeated_enum` -> `impl_from_repeated_copy` since the enum
references were just simply deref copied
- `try_from_repeated_message` -> `impl_try_from_repeated`
- Simplified the implementation of `from_repeated_enum`
- Added `*-current()` functions to `Artist` to get the list of current
versions / releases of each album
- This is useful since the `AlbumGroups` can contain multiple versions
/ releases of the same album
- Derive `Default` trait for the vec / hashmap wrapper types in
`librespot-metadata`
- The wrapped types (`Vec` / `Hashmap`) implement Default, so the
wrapper types should as well
* Expose all fields of recent protobufs
* Add support for user-scoped playlists, user root playlists and
playlist annotations
* Convert messages with the Rust type system
* Attempt to adhere to embargos (tracks and episodes scheduled for
future release)
* Return `Result`s with meaningful errors instead of panicking on
`unwrap`s
* Add foundation for future playlist editing
* Up version in connection handshake to get all version-gated features
