Add a section on the async ecosystem to showcase crates that use async-std

Author: mehcode

README.md

@@ -120,6 +120,20 @@ documentation] on how to enable them.
 [cargo-add]: https://github.com/killercup/cargo-edit
 [features documentation]: https://docs.rs/async-std/#features
 
+## Ecosystem
+ 
+ * [async-tls](https://crates.io/crates/async-tls) — Async TLS/SSL streams using **Rustls**. 
+  
+ * [async-native-tls](https://crates.io/crates/async-native-tls) — **Native TLS** for Async. Native TLS for futures and async-std.
+ 
+ * [async-tungstenite](https://crates.io/crates/async-tungstenite) — Asynchronous **WebSockets** for async-std, tokio, gio and any std Futures runtime.
+ 
+ * [Tide](https://crates.io/crates/tide) — Serve the web. A modular **web framework** built around async/await.
+
+ * [SQLx](https://crates.io/crates/sqlx) — The Rust **SQL** Toolkit. SQLx is a 100% safe Rust library for Postgres and MySQL with compile-time checked queries.
+
+ * [Surf](https://crates.io/crates/surf) — Surf the web. Surf is a friendly **HTTP client** built for casual Rustaceans and veterans alike.
+ 
 ## License
 
 <sup>