adds copper

Author: gbin

README.md

@@ -21,6 +21,7 @@ library.
 
 ## Bincode in the Wild
 
+* [copper-rs](https://github.com/copper-project/copper-rs): copper-rs uses Bincode.
 * [google/tarpc](https://github.com/google/tarpc): Bincode is used to serialize and deserialize networked RPC messages.
 * [servo/webrender](https://github.com/servo/webrender): Bincode records WebRender API calls for record/replay-style graphics debugging.
 * [servo/ipc-channel](https://github.com/servo/ipc-channel): IPC-Channel uses Bincode to send structs between processes using a channel-like API.