在mac osx上安装RVM和ZSH后出现如下警告：
Warning! PATH is not properly set up, $GEM_HOME is not set,
usually this is caused by shell initialization files - check them for 'PATH=...' entries,
it might also help to re-add RVM to your dotfiles: 'rvm get stable --auto-dotfiles'
打开 ~/.zshrc文件，找到PATH设置
export PATH="/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Users/bruce.wu/.rvm/bin"
在最前面加上$PATH就好了，修改之后如下
export PATH="$PATH:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Users/bruce.wu/.rvm/bin"
