title: Cloning only a subdirectory with git
body: <p>I have a git repository that includes subdirectories. Example dirA/dirB.
  Is there any way to do a <code>git clone</code> on a Unix server to pull only files from a subdirectory (dirB)?</p>
  
  <p>Is there some other git command other than clone that will do this?</p>
  
  <p>How do I git a specific file?</p>