Common types that are used in the different [matrix-sdk] layers.

**NOTE:** These are common dependencies for the different [matrix-sdk] layers,
you're probably interested in the main
[matrix-sdk](https://docs.rs/matrix-sdk/) crate.

[matrix-sdk]: https://github.com/matrix-org/matrix-rust-sdk/
[Matrix]: https://matrix.org/
[Rust]: https://www.rust-lang.org/