message: nix oneOrMoreOf() reference
diff: @@ -2,7 +2,6 @@ import React from 'react'
  import PropTypes from 'prop-types'
  import {arc as Arc, pie as Pie} from 'd3-shape'
  import DonutSlice from './DonutSlice'
  -import {oneOrMoreOf} from './props'
  import {withSystemProps} from './system-props'
  function DonutChart(props) {
  @@ -41,7 +40,7 @@ DonutChart.defaultProps = {
  DonutChart.propTypes = {
  // require elements, not mixed content: <DonutSlice>, <title>, etc.
  - children: oneOrMoreOf(PropTypes.element),
  + children: PropTypes.oneOfType([PropTypes.element, PropTypes.arrayOf(PropTypes.element)]),
  data: PropTypes.objectOf(PropTypes.number),
  size: PropTypes.number
  }
  