title: git push heroku master says "Everything up-to-date", but the app is not current
body: <p>I have an app on Heroku that is running old code.  I've made a small change and committed the change.  I then ran</p>
  
  <pre><code>git push heroku master
  </code></pre>
  
  <p>It'll say</p>
  
  <pre><code>Fetching repository, done.
  Everything up-to-date
  </code></pre>
  
  <p>But if I go and look at the app, it's all old code.  I did revert the site back to another version in Heroku about 15 days ago, but pushed updates to it since then and they worked.</p>
  
  <p>Why is heroku not getting the most current files from my github repository?  Is there a way to just reset the app and push the files from github again?  I have production data in the database so I do NOT want to touch it.</p>
  
  <p>Thanks in advance!!</p>