快速上手React Router
由 Lesson 1 - Setting Up 開始.
每一章節的課程皆是一個完整可執行的app，且包含了前一章節課程中的實作結果，因此我們可以藉由
cd lessons/<lesson-folder>
npm install安裝相關套件,
並在每一個課程章節資料夾中執行適當的NPM scripts來進行。
Missing stuff that will come eventually, hopefully ... maybe.
- an app that isn't completely pointless
- egghead.io videos
- code splitting
- location state
- data integration