安装
yum install docker-io
启动docker
service docker start
开机启动
chkconfig docker on
结束！！！！
but:
ps aux|grep docker
未发现任何进程，虽然service doker start 显示OK并未报任何错，这不怪doker，官网说的很清楚
Docker requires a 64-bit OS and version 3.10 or higher of the Linux
kernel.
但猜测不是这个原因，程序都没启动起来。
查看日志 /var/log/docker 发现如下错误。
/usr/bin/docker: relocation error: /usr/bin/docker: symbol
dm_task_get_info_with_deferred_remove, version Base not defined in
file libdevmapper.so.1.02 with link time reference
so:
yum upgrade device-mapper-libs
service docker start发现正常启动，查看日志，只有kernel版本的warning了！
安装 splash
相关链接：
https://github.com/scrapinghub/splash
http://splash.readthedocs.io/en/stable/
docker pull scrapinghub/splash
docker run -p 5023:5023 -p 8050:8050 -p 8051:8051 scrapinghub/splash
Splash is now available at 0.0.0.0 at ports 8050 (http), 8051 (https)
and 5023 (telnet).
