title: What is the GPars default pool size?
body: <p>I thought this would have been an easy thing to find but I've failed.</p>
  
  <p>If I use GPars in my Groovy application and I don't specify a pool size how many threads will be created? Is there a default pool size without setting one?</p>
  
  <pre><code>// How many threads will be created? What is the default pool size?
  GParsExecutorsPool.withPool {
      // do stuff...
  }
  </code></pre>