title: Ruby rest client array of params
body: <p>I'm updating my rest-client gem from 1.8 to 2.0.</p>
  
  <p>On 1.8 it sends an array of params on a get request as <code>my-url?ids=1,2,3,4</code>.
  But on 2.0 it uses duplicated keys like <code>my-url?ids=1&amp;ids=2&amp;ids=3</code>. For reasons beyond the context of this question, our back end does NOT support the new multiple keys syntax (ok, it supports it, but we'll have to make a big refactor). So I'd like to know if there's a way to use the 2.0 client version and keep sending get array requests with only one key and separated by comma as before?</p>