https://flutter.dev/docs/development/ui/widgets/material
https://github.com/google/built_value.dart
https://pub.dev/packages/rebloc
https://www.didierboelens.com/2019/04/bloc---scopedmodel---redux---comparison/
- View Product Detail
- Add Product to Cart
- Remove Product from Cart
- Login
- Fetch and Add Random New Product
- Logout