修改pip源

http://www.cnblogs.com/hushaojun/p/4606986.html

mkdir -p ~/.pip/

vi ~/.pip/pip.conf

[global]
trusted-host=mirrors.aliyun.com
index-url=http://mirrors.aliyun.com/pypi/simple/

• http://pypi.v2ex.com/simple/
• http://pypi.douban.com/simple/
• http://mirrors.aliyun.com/pypi/simple/