title: Recursively batch process files with pngquant
body: <p>I have a lot of images that I would like to process with pngquant. They are organized in a pretty deep directory structure, so it is very time-consuming to manually <code>cd</code> into every directory and run <code>pngquant -ext .png -force 256 *.png</code></p>
  
  <p>Is there a way to get this command to run on every *.png in every directory within the current one, as many layers deep as necessary?</p>