General refactor

[danilobjr]

• Modernize codebase
  • Convert some components to Stateless Functional Components
  • Satisfy editorconfig rules
• Import React stuff individually instead of use React.Something
• Use async/await instead of Promises
• Use ... (spred operator) instead of Object.assign
• Use the new React Context API
• Use tslint
• Use tslib
• Use import aliases
• Components displayName
• Solve TODOs