title: Permission denied (publickey) when deploying heroku code. fatal: The remote end hung up unexpectedly
body: <p>I'm attempting to deploy my code to heroku with the following command line:</p>
  
  <pre><code>git push heroku master
  </code></pre>
  
  <p>but get the following error:</p>
  
  <pre><code>Permission denied (publickey).
  fatal: The remote end hung up unexpectedly
  </code></pre>
  
  <p>I have already uploaded my public SSH key, but it still comes up with this error.</p>