message: Add missing import in Moment locale example
  according to locales have to be imported before being used.
diff: import React from 'react';
  import moment from 'moment';
  +import 'moment/locale/fr'; // this is the important bit, you have to import the locale your'e trying to use.
  import MomentUtils from 'material-ui-pickers/utils/moment-utils';
  import MuiPickersUtilsProvider from 'material-ui-pickers/utils/MuiPickersUtilsProvider';
  