Revert "add note about socket.io 2.0 and unicode"

This reverts commit 43d5455e823b5af15a3781c9a2a73ded7c74aac6.

README.md

@@ -51,15 +51,12 @@ SocketIOClient* socket = [[SocketIOClient alloc] initWithSocketURL:url config:@{
 ```
 
 ## Features
-- Supports socket.io 1.0+<sup>a</sup>
+- Supports socket.io 1.0+
 - Supports binary
 - Supports Polling and WebSockets
 - Supports TLS/SSL
 - Can be used from Objective-C
 
-_<sub>a: For socket.io 2.0+ servers, client versions less than v10.0 must pass .doubleEncodeUTF8(false) as a config, 
-otherwise unicode will become garbled</sub>_
-
 ## Installation
 Requires Swift 3/Xcode 8.x