update README

README.md

@@ -1,25 +1,40 @@
 shadowsocks-libev
 =================
 
-shadowsocks-libev is a lightweight obfuscated scoks5 proxy.
+Intro
+-----
 
-It is a port of [shadowsocks](https://github.com/clowwindy/shadowsocks).
+Shadowsocks-libev is a lightweight obfuscated scoks5 proxy for embedded devices
+like routers and mobile phones.
 
-Only the client is ported. Please use [shadowsocks-nodejs](https://github.com/clowwindy/shadowsocks-nodejs) 
-to setup your server.
+It is a port of [shadowsocks](https://github.com/clowwindy/shadowsocks) with
+only client part ported.
 
-installation
+To setup your own server, please refer to
+[shadowsocks ports](https://github.com/clowwindy/shadowsocks/wiki/Ports-and-Clients) 
+for more information.
+
+Features
+--------
+
+Shadowsocks-libev is writen in C and only depends on
+[libev](http://software.schmorp.de/pkg/libev.html). When statically linked and
+packaged for OpenWRT, the total binary size is 23KB. In normal usage, the memory 
+consumption is about 600KB and the CPU utilization is no more than 5%, which is tested
+in a low-end router (Buffalo WHR-G300N V2 with a 400MHz MIPS CPU, 32MB memory
+and 4MB flash).
+
+Installation
 ------------
 
 Build the binary like this:
 
 ```bash
-    sudo apt-get install build-essential autoconf libtool libev-dev libssl-dev
-
+    sudo apt-get install build-essential autoconf libtool libev-dev
     ./configure && make
 ```
 
-usage
+Usage
 -----
 
 ```