title: Move tag one commit ahead
body: <p>I have a repository with only one branch (<code>master</code>). I'm the only contributor to my repo.</p>
  
  <p>I've recently added a <code>tag</code>, both locally and pushed to GitHub. After making what I though was the last necessary commit, but now I realize I should have made one more change/commit.</p>
  
  <p>So what I have is:</p>
  
  <pre><code>commit 124
  commit 125
  commit 126 &lt;-- tag v1.0
  commit 127
  </code></pre>
  
  <p>and I want to move the <code>v1.0</code> tag to the next commit, ie: <code>127</code>, both locally and in GitHub.</p>
  
  <p>How can I do that?</p>