Beta Update

• Features
  • Bump websocket-extensions from 0.1.3 to 0.1.4
  • Bump lodash from 4.17.15 to 4.17.19
  • Bump elliptic from 6.5.2 to 6.5.3
  • Bump http-proxy from 1.18.0 to 1.18.1
  • Bump highlight.js from 9.18.1 to 9.18.5
  • Bump elliptic from 6.5.3 to 6.5.4

Beta Fixing

• Features
  • Import Yarn as a package manager
  • Update .gitignore for using Yarn
  • Update commands of serving and building in README.md
  • Import Prettier as code formatter
  • Update TSLint checking rules

Beta Release

• Features
  • Enable to add, remove, and edit the item
  • Enable to show the different status of items (i.e., all, active, done)
  • Enable to show the progress of current finishing
  • Enable to show the count of items in each status
  • Enable local storage for storing the list