title: How to specify a default user agent for okhttp 2.x requests
body: <p>I am using okhttp 2.0 in my Android app and didn't find a way to set some common User Agent for all outgoing requests.</p>
  
  <p>I thought I could do something like</p>
  
  <pre><code>OkHttpClient client = new OkHttpClient();
  client.setDefaultUserAgent(...)
  </code></pre>
  
  <p>...but there's no such method or similar.
  Of course I could provide some extension utility method which would wrap a RequestBuilder to attach <code>.header("UserAgent")</code> and then I would use it for building all my requests, but I thought maybe I missed some existing and simpler way?</p>