http://www.dwhd.org/20150525_182436.html
http://www.xinsaisai.com/ec2-ubuntu-pptpd-vpn.html
https://segmentfault.com/a/1190000003101075
* Python版一键安装脚本
https://teddysun.com/342.html
step1. 安装喜欢的桌面环境
sudo apt-get install ubuntu-desktop #GNOME
sudo apt-get install kubuntu-desktop #KDE
sudo apt-get install xubuntu-desktop #xfce
step2. 安装VNC服务
sudo apt-get install vnc4server