v2.18.0

New

• Add support for flow >=0.53 and the new react definitions (#209).
• Resolve Object.keys in PropType.oneOf() (#211).
  For example:

  Component.propTypes = { foo: PropTypes.oneOf(Object.keys({ a: 1, b: 2 }))};
  // react-docgen will now correctly extract the type of foo being "a" or "b"