1 安装 composer
curl -sS https://getcomposer.org/installer | php
2 添加到环境变量
mv composer.phar /usr/local/bin/composer
ln -s /usr/local/php /usr/local/bin/php
centos 安装 composer
原文：http://www.cnblogs.com/jackspider/p/6292432.html
