Use the new connectTimeout in request

* I added a connectTimeout option to request that lets us time out quickly
  when the TCP connection is not accepted:
  https://github.com/gwicke/request/commit/9a028bfd4652232c2aa8463f82afe0cff76548f1

* Use this option for all API requests with a timeout of 5 seconds (matching
  Varnish defaults)

* Also warn about request failures using env.log

Change-Id: I945d904aad648a54be752d31c294fde62ee8da7d