composer 修改为阿里云国内镜像

配置只在当前项目生效
composer config repo.packagist composer https://mirrors.aliyun.com/composer/
取消当前项目配置
composer config --unset repos.packagist
配置全局生效
composer config -g repo.packagist composer https://mirrors.aliyun.com/composer/
取消全局配置
composer config -g --unset repos.packagist

配置代理：