title: How to get `git-p4 sync` to work?
body: <p>I've successfully created a git branch called 'scaffold' by using <code>git-p4.py clone</code>.</p>
  
  <p>I now want to sync the latest Perforce changes into the git branch so I'm trying <code>git-p4.py sync  --branch=scaffold</code> but all that happens is the output of the following:</p>
  
  <pre><code>Syncing with origin first, using "git fetch origin"
  Creating/updating branch(es) in refs/remotes/p4/ based on origin branch(es)
  Performing incremental import into scaffold git branch
  Depot paths: //depot/depot/path/to/code/
  No changes to import!
  </code></pre>
  
  <p>After that, <code>git status</code> says <code>nothing to commit (working directory clean)</code>.</p>
  
  <p>How do I get this to work?</p>