update readme

@@ -131,7 +131,7 @@ Supported operating systems and hardware:
 17. support live stream transcoding by ffmpeg.<br/>
 18. support ffmpeg filters(logo/overlay/crop), x264 params.<br/>
 19. support audio transcode only, speex/mp3 to aac<br/>
-20. support http callback api hooks(for authentication).<br/>
+20. support http callback api hooks(for authentication and injection).<br/>
 21. [plan] support network based cli and json result.<br/>
 22. [plan] support bandwidth test api and flash client.<br/>
 23. [plan] support adobe flash refer/token/swf verification.<br/>