Get a random user agent string
uas.json contains a list of user agent strings from http://www.useragentstring.com/pages/useragentstring.php?name=All
$ npm install --save random-uas
const randomUas = require('random-uas');
console.log(randomUas()); // 'Mozilla/5.0 (Windows; U; Win95; en-US; rv:1.5) Gecko/20031007 Firebird/0.7'