Amazon-pa-api50: Create Config instance

amazon-pa-api50-config

// By Default all resources and will connect to United States
let myConfig = new Config();
// if you want other country then united states.
let myConfig = new Config(undefined, country.UnitedKingdom);
// if you want custom resources.
// this custom `resources.Offers` will be set default to all of your search. You can customize the resources in your search specific function also.
let myConfig = new Config(resources.Offers);
// if you want custom resources with different country
let myConfig = new Config(resources.ItemInfo, country.Canada);