Add rustc minimum version to readme
In the light of we should make clear what's the minimum rustc version is OpenMLS requires.
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[![OpenMLS List][list-image]][list-link]
+![Rust Version][rustc-image]
A WIP Rust implementation of [Messaging Layer Security](https://github.com/mlswg/mls-protocol/blob/master/draft-ietf-mls-protocol.md) based on draft 9+.
@@ -27,6 +28,8 @@ OpenMLS relies on [EverCrypt](https://github.com/project-everest/hacl-star/tree/
## Development
+OpenMLS requires at least Rust 1.50.0.
+
### Build
- run `cargo build`
@@ -73,3 +76,4 @@ OpenMLS adheres to the [Contributor Covenant](https://www.contributor-covenant.o
[chat-link]: https://openmls.zulipchat.com
[list-image]: https://img.shields.io/badge/mailing-list-blue.svg
[list-link]: https://groups.google.com/u/0/g/openmls-dev
+[rustc-image]: https://img.shields.io/badge/rustc-1.50+-blue.svg
