code: function checkForUpgrade(ref, data, locals) {
    return utils.getSchema(ref)
      .then(schema => {
        // If version does not match what's in the data
        if (schema && schema._version && schema._version !== data._version) {
          return module.exports.upgradeData(schema._version, data._version, ref, data, locals);
        }
  
        return bluebird.resolve(data);
      });
  }
docs: Grab the schema for the component and check if the schema
  and data versions do not match. If they do we don't need
  to do anything, otherwise the upgrade process needs to be
  kicked off.
  
  @param  {String} ref
  @param  {Object} data
  @param  {Object} locals
  @return {Promise}