How to use the pouchdb.setMaxListeners function in pouchdb

var Mailer = require('../lib/mailer');
var util = require('../lib/util');
var seed = require('pouchdb-seed-design');
var request = require('superagent');
var config = require('./test.config.js');

var chai = require('chai');
var sinon = require('sinon');
var expect= chai.expect;
chai.use(require('sinon-chai'));

var dbUrl = util.getDBURL(config.dbServer);

var emitter = new events.EventEmitter();

PouchDB.setMaxListeners(20);
var userDB = new PouchDB(dbUrl + "/superlogin_test_users");
var keysDB = new PouchDB(dbUrl + "/superlogin_test_keys");

var testUserForm = {
  name: 'Super',
  username: 'superuser',
  email: 'superuser@example.com',
  password: 'superlogin',
  confirmPassword: 'superlogin',
  age: '32',
  zipcode: 'ABC123'
};

var emailUserForm = {
  name: 'Awesome',
  email: 'awesome@example.com',