title: Exclude directory during jenkins checkout
body: <p>I have 20 directories under trunk</p>
  
  <pre><code>/trunk/a1
  /trunk/a2
  /trun/a3
  ..
  ..
  /trunk/a20
  </code></pre>
  
  <p>How to exclude (not include) some (arbitrary directories during Jenkins checkout.
  For example, I want to have all the directories under trunk except <strong>/trunk/a3/b1</strong>
  How to do this?</p>
  
  <p>I already found an answer in <a href="https://stackoverflow.com/questions/192824/svn-checkout-ignore-folder">SVN checkout ignore folder</a> but this is not possible under Jenkins. Need a much simpler solution where I don't know the number of directories under trunk except the one I want to exclude. </p>
  
  <p>Also how to add a custom svn checkout.Let's say I want to execute svn command line tool to do the checkout?</p>