This change makes it possible for TypeScript users to use the d.ts
we create at build time. This addresses the very popular #503, but at a cost.
BREAKING CHANGE: This library is now optimized for es6 modules. In previous
versions you would import the library like this:
const google = require('googleapis');
In this and future versions, you must use a named import:
const {google} = require('googleapis');
You may also reference the type to instantiate a new instance:
const {GoogleApis} = require('googleapis');
const google = new GoogleApis();