Timekeeper 2.0

Complete rewrite of the library written for react 16.8+ in hooks. New features include:

• 24 hour mode (#4)
• customizable done button (via render props) (#20)
• customizable coarse minutes (#20)
• typescript support
• improved dev environment + updated libraries
  • updated dependencies - webpack, jest,
  • replaced reaction motion with react spring, radium with emotion
  • eslint + prettier
• better clock hand animations + minor performance improvements