title: Gulp copying empty directories
body: <p>In my <em>gulp</em> build I've made a task that runs <em>after</em> all compiling, uglifying and minification has occurred. This task simply copies everything from the <em>src</em> into the <em>dest</em> directory that hasn't been touched/processed by earlier tasks. The little issue I'm having is that this results in empty directories in the <em>dest</em> directory.</p>
  
  <p>Is there a way to tell the <code>gulp.src</code> glob to only include files in the pattern matching (like providing the <code>'is_file'</code> flag)?</p>
  
  <p>Thanks.</p>