title: Concat a single file to every file in a directory using grunt
body: <p>Using Grunt, I want to concat one file to all of the files in a build directory. The purpose of doing so is to append (or potentially prepend) IE specific CSS files to a build CSS file.</p>
  
  <p>To task this:</p>
  
  <pre><code>build/
    file1.css
    file2.css
    file3.css
  </code></pre>
  
  <p>And create this:</p>
  
  <pre><code>build/
    file1.css
    file1.ie.css
    file2.css
    file2.ie.css
    file3.css
    file3.ie.css
  </code></pre>
  
  <p>I thought that the expand option might be what I was looking for but I can't figure out how to get it to do what I want. </p>