update readme

@@ -5,8 +5,9 @@ for the best conceptual integrity and the simplest implementation.
 
 SRS delivers rtmp/hls live on x86/x64/arm/mips linux, 
 supports origin/edge/vhost and transcode/ingest and dvr/forward 
-and http-api/http-callback/reload, exports srs-librtmp, 
-with EN/CN wiki and the most simple architecture.
+and http-api/http-callback/reload, introduces tracable 
+session-oriented log, exports client srs-librtmp, 
+provides EN/CN wiki and the most simple architecture.
 
 Download from github.io: 
 [Centos6-x86_64](http://winlinvip.github.io/srs.release/releases/files/SRS-CentOS6-x86_64-1.0.0.zip)