iOS pod install时，遇到了Insecure wor

今天pod install时，遇到了Insecure world writable dir的异常警告，本着好记性不如烂笔头的原则，记录下，以备不时之需

/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.5.3/lib/cocoapods/executable.rb:89:
warning: Insecure world writable dir /usr/local in PATH, mode 040777

要去除这个警告，需要更改/usr/local的权限即可，命令如下：

sudo chmod go-w /usr/local