title: Git: whole file to stdout
body: <p>Is there a command that can take a ref and a file path, and output the full contents of the file as it was at that commit to STDOUT?</p>
  
  <p>Eg. Something like this:</p>
  
  <pre><code>git show-me-the-file HEAD~2 some/file | do_something_with_piped_output_here
  </code></pre>