Update readme

README.md

 # dataplay2
 Please refer to my blog(Chinese) for a simple introduction http://my.oschina.net/taogang/blog/630632
 
-Add docker build @ https://github.com/gangtao/dataplay2/tree/master/docker in case you have trouble to run it
+Add docker build @ https://github.com/gangtao/dataplay2/tree/master/docker in case you have trouble to run it.
 
-install docker
 ```
 cd dataplay2/docker
 docker build -t dataplay:latest .
-docker run -p 5000:5000  naughtytao/dataplay
+docker run -p 5000:5000 dataplay
+```
+
+or you can direcly run
+```
+docker run -p 5000:5000 naughtytao/dataplay
 ```