Optimize ES6 usage in main app and "vanilla" app version

[ayubadiputra]

Consider to use Object desctructuring

• Consider to use Object destructuring App.js:81
• Consider to use Object destructuring actions/index.jsx
• Consider to use Object destructuring components/icon/index.jsx
• Consider to use Object destructuring components/AddTodo.jsx
• Consider to use Object destructuring components/TodoItem.jsx
• Consider to use Object destructuring components/TodoList.jsx

Specific issues

• Remove unused props App.js:86
• Create separated button component components/TodoItem.jsx:209
• Consider to use spread variables components/TodoList.jsx:57
• Simplify this section components/TodoList.jsx:78
• Set proper variables name
• Wrong implementation stores/index.jsx:168 and stores/index.jsx:193