This is a rebased version of #2410 with review notes addressed and an additional clearTimeout that either didn't exist or was missed in the original pr.

From @elmigranto's #2410

Calling #abort() does not clear timeout, process hangs until timer is triggered. There are couple of places this is done correctly, #abort() happens not to be one of them. There are couple of relevant issues and PRs from years ago.

Sample script to reproduce:

'use strict';
const request = require('request');
const started = Date.now();
const printTime = label => () => console.log('%d ms\t%s', Date.now() - started, label);

const req = request({
  uri: 'http://example.com',
  timeout: 2500
}, printTime('callback'));

setTimeout(() => {
  req.abort();
  printTime('aborted')();
}, 10);

process.on('exit', printTime('exit'));

// 27 ms    aborted
// 2519 ms  callback
// 2521 ms  exit

Let's close this one finally. Can any of you guys help, please? @mikeal @simov

closes @2410