HomeBrew 安装 PHP7.1
$ brew update
$ brew tap homebrew/dupes
$ brew tap homebrew/php
$ brew update
$ brew install php71
安装好后生成的配置文件都在 /usr/local/etc/php/7.1 目录里，分别如下：
php.ini /usr/local/etc/php/7.1/php.ini
php-fpm.conf /usr/local/etc/php/7.1/php-fpm.conf
php, phpize, php-config ls /usr/local/opt/php71/bin
php-fpm /usr/local/opt/php71/sbin/php-fpm
