title: git-cat-file fails with no other information
body: <pre><code>git cat-file -p master^{tree}
  </code></pre>
  
  <p>while this is straight from the pro git book, pg 226, it doesn't work for me. I just get back the command help text with no other errors or text:</p>
  
  <pre><code>D:\Users\jon\Documents\GitHub\FilePathContextMenu [master]&gt; git cat-file -p mast
  er^{tree}
  usage: git cat-file (-t|-s|-e|-p|&lt;type&gt;|--textconv) &lt;object&gt;
     or: git cat-file (--batch|--batch-check) &lt; &lt;list_of_objects&gt;
  
  &lt;type&gt; can be one of: blob, tree, commit, tag
      -t                    show object type
      -s                    show object size
      -e                    exit with zero when there's no error
      -p                    pretty-print object's content
      --textconv            for blob objects, run textconv on object's content
      --batch[=&lt;format&gt;]    show info and content of objects fed from the standard
   input
      --batch-check[=&lt;format&gt;]
                            show info about objects fed from the standard input
  </code></pre>