remove mention of tidwall/SwiftWebSocket

Author: or-else

README.md

@@ -106,7 +106,7 @@ When you register a new account you are asked for an email address to send valid
   * Bindings for various programming languages:
     * Javascript with no external dependencies.
     * Java with dependencies on [Jackson](https://github.com/FasterXML/jackson) and [Java-Websocket](https://github.com/TooTallNate/Java-WebSocket). Suitable for Android but with no Android SDK dependencies.
-    * Swift with dependency on [SwiftWebSocket](https://github.com/tidwall/SwiftWebSocket).
+    * Swift with no external dependencies.
     * C/C++, C#, Go, Python, PHP, Ruby and many other languages using [gRPC](https://grpc.io/docs/languages/).
   * Choice of a database backend: MySQL, RethinkDB, MongoDB.