message: tweak Position exports
diff: import React from 'react'
  import {withSystemProps, LAYOUT, POSITION} from './system-props'
  -const Position = withSystemProps('div', LAYOUT.concat(POSITION))
  +export const Position = withSystemProps('div', LAYOUT.concat(POSITION))
  function withPosition(position) {
  const WithPosition = props => <Position {...props} position={position} />
  @@ -13,9 +13,7 @@ function withPosition(position) {
  return WithPosition
  }
  -const Absolute = withPosition('absolute')
  -const Fixed = withPosition('fixed')
  -const Relative = withPosition('relative')
  -const Sticky = withPosition('sticky')
  -
  -export {Position, Absolute, Fixed, Relative, Sticky}
  +export const Absolute = withPosition('absolute')
  +export const Fixed = withPosition('fixed')
  +export const Relative = withPosition('relative')
  +export const Sticky = withPosition('sticky')
  