Add note about aws_lambda_events crate (#42)

* Add note about `aws_lambda_events` crate

As mentioned in #12

* Use backticks for crate name

Author: LegNeato

README.md

@@ -102,6 +102,10 @@ pub type Handler<E, O> = fn(E, Context) -> Result<O, error::HandlerError>;
 
 Optionally, you can pass your own instance of Tokio runtime to the `lambda!()` macro. See our [`with_custom_runtime.rs` example](https://github.com/awslabs/aws-lambda-rust-runtime/tree/master/lambda-runtime/examples/with_custom_runtime.rs)
 
+## AWS event objects
+
+This project does not currently include Lambda event struct defintions though we [intend to do so in the future](https://github.com/awslabs/aws-lambda-rust-runtime/issues/12). Instead, the community-maintained [`aws_lambda_events`](https://crates.io/crates/aws_lambda_events) crate can be leveraged to provide strongly-typed Lambda event structs. You can create your own custom event objects and their corresponding structs as well.
+
 ## Custom event objects
 
 To serialize and deserialize events and responses, we suggest using the use the [`serde`](https://github.com/serde-rs/serde) library. To receive custom events, annotate your structure with Serde's macros: