message: only require simple_storage when used
diff: *
  */
  var mustache = require('mustache');
  -var simple_storage = require(__dirname + '/storage/simple_storage.js');
  var ConsoleLogger = require(__dirname + '/console_logger.js');
  var LogLevels = ConsoleLogger.LogLevels;
  var ware = require('ware');
  @@ -1734,6 +1733,7 @@ function Botkit(configuration) {
  }
  } else if (configuration.json_file_store) {
  botkit.log('** Using simple storage. Saving data to ' + configuration.json_file_store);
  + var simple_storage = require(__dirname + '/storage/simple_storage.js');
  botkit.storage = simple_storage({
  path: configuration.json_file_store
  });
  