Homework for Server

please follow flow below

1. Fork to you own github.
2. Follow steps in document to finish the homework.
3. Every week will check the homework, please make sure things below before you submit.
   • Every step need a branch, each bracnh need to pass Travis CI, and make a PR to my repo master branch, to pass the CI for each branch, please follow the document -> https://docs.travis-ci.com/user/customizing-the-build
   • When you pass Travis CI, please update you README and have a sticky image -> on the top of your README.