title: Change remote 'origin' to 'upstream' with Git
body: <p>I've cloned a Git repo from the original source's <code>upstream</code> <code>master</code> repo to my local machine.
  <br/><code>git remote -v</code> returns:</p>
  <pre><code>origin  https://github.com/project.git (fetch)
  origin  https://github.com/project.git  (push)
  </code></pre>
  <p>But I now know that I need to instead fork this <code>upstream</code> <code>master</code> branch to my personal GitHub account, clone that, create a new branch, and begin coding (so that I'm not making changes directly to the <code>upstream</code> repo, but rather to my own forked <code>origin</code> repo). I've forked the <code>upstream</code> <code>master</code> to my GitHub profile, but don't know how to proceed. I need to get <code>git remote -v</code> to look like this:</p>
  <pre><code>origin    https://github.com/myGitHubProfile/project.git (fetch)
  origin    https://github.com/myGitHubProfile/project.git (push)
  upstream    https://github.com/project.git (fetch)
  upstream    https://github.com/project.git  (push)
  </code></pre>
  <p>How can I accomplish this, given that I've already cloned the <code>upstream</code> <code>master</code> from the original source and it's already set as <code>origin</code>?</p>