message: Add makeRegistrationUrl to proptypes
diff: @@ -65,6 +65,9 @@ module.exports = React.createClass({
  // displayname, if any, to set on the device when logging
  // in/registering.
  defaultDeviceDisplayName: React.PropTypes.string,
  +
  + // A function that makes a registration URL
  + makeRegistrationUrl: React.PropTypes.func.isRequired,
  },
  childContextTypes: {
  