Solved packet encode/decode boilerplate code issue

Something as simple as forgetting the reset() when encoding would cause lots of problems which could go unnoticed. This should be fully backwards-compatible but needs more tests.

src/pocketmine/network/mcpe/protocol/ClientToServerHandshakePacket.php

@@ -35,12 +35,11 @@ class ClientToServerHandshakePacket extends DataPacket{
 		return true;
 	}
 
-	public function decode(){
+	public function decodePayload(){
 		//No payload
 	}
 
-	public function encode(){
-		$this->reset();
+	public function encodePayload(){
 		//No payload
 	}