Test Expose add and add2

exposeAdd.js

var privateState = require('privatestate');
var utils = require('./utils');

describe('utils#add', function() {
  it('should add two numbers', function() {
    var add = privateState.getForTesting(utils, 'add');
    var actual = add(2, 4);
    assert.equal(actual, 6);
  });
});