2.0

• Allow dev dependencies in webpack.config.js.
• Add new base rule: prefer-arrow-callback.
• Add new react rules:
  • jsx/curly-brace-presence
  • react/no-access-state-in-setstate
  • react/no-unused-state
  • react/no-typos
  • react/no-direct-mutation-state
• Adapted react/jsx-sort-props to sort reserved props first (since an upstream bug is now fixed).
• Update dev and peer deps.
• Update README to reflect a recent change in the linter-eslint UI.