Update JavaDocs

Author: marci4

src/main/java/org/java_websocket/drafts/Draft_6455.java

@@ -514,7 +514,7 @@ private Framedata translateSingleFrame( ByteBuffer buffer ) throws IncompleteExc
      * Translate the buffer depending when it has an extended payload length (126 or 127)
      * @param buffer the buffer to read from
      * @param optcode the decoded optcode
-     * @param oldPayloadlength the current payload length
+     * @param oldPayloadlength the old payload length
      * @param maxpacketsize the max packet size allowed
      * @param realpacketsize the real packet size
      * @return the new payload length