add to database mongoose code example

Example 1: mongoose setup

// getting-started.js
const mongoose = require('mongoose');
mongoose.connect("mongodb://localhost:27017/name", { useUnifiedTopology: true, useNewUrlParser: true });

Example 2: node js + mongoose

await mongoose.connect('mongodb://localhost/my_database', {  useNewUrlParser: true,  useUnifiedTopology: true});