是什么原因导致错误:EACCES:权限被拒绝，访问'/usr/local/lib/node_modules'?
npm ERR! path /usr/local/lib/node_modules
npm ERR! code EACCES
npm ERR! errno -13
npm ERR! syscall access
npm ERR! Error: EACCES: permission denied, access '/usr/local/lib/node_modules'
npm ERR! { Error: EACCES: permission denied, access '/usr/local/lib/node_modules'
npm ERR! errno: -13,
npm ERR! code: 'EACCES',
npm ERR! syscall: 'access',
npm ERR! path: '/usr/local/lib/node_modules' }
npm ERR!
npm ERR! Please try running this command again as root/Administrator.
npm ERR! A complete log of this run can be found in:
npm ERR! /Users/macbookmd101/.npm/_logs/2018-02-21T16_26_08_421Z-debug.log
