Update README.md

Author: HessianZ

README.md

@@ -6,17 +6,21 @@ A simple proxy based on goproxy.
 一个基于goproxy的简单http代理，可以指定出口IP地址。
 
 ### Usage
+```
 Usage of ./daisy-proxy:
   -dns="8.8.8.8 8.8.4.4": dns servers
   -if="": out interface
   -ip="": out address
   -listen="localhost:8080": listen on this address and port
   -verbose=false: verbose output
   -h   : show help usage
-  
+```
+
 ### Example
+```
 ./daisy-proxy -if ppp0
 2015/04/11 10:15:40 DaisyProxy listen on localhost:8080 outgoing from 10.0.0.60
+```
 
 ### Download