title: <tag> property confusion (SCM, release:prepare)
body: <p>What is the difference between <a href="https://maven.apache.org/scm/maven-scm-plugin/tag-mojo.html" rel="nofollow noreferrer"><code>scm:tag</code></a>:</p>
  
  <pre><code>&lt;scm&gt;
      &lt;connection&gt;scm:git:code.stuff.com/scm/project/repo.git&lt;/connection&gt;
      &lt;developerConnection&gt;scm:git:ssh://git@code.stuff.com:7999/project/repo.git&lt;/developerConnection&gt;
      &lt;tag&gt;HEAD&lt;/tag&gt;
  &lt;/scm&gt;
  </code></pre>
  
  <p>and <a href="http://maven.apache.org/maven-release/maven-release-plugin/prepare-mojo.html#tag" rel="nofollow noreferrer"><code>release:prepare:tag:</code></a>?</p>
  
  <p>I read that during the <code>release:prepare</code> goal, user is prompted with the desired tag-name to stick; after preparation is successfully completed, Maven will tag the release candidate in the VCS with the passed name. At this point, what is the use of <code>scm:tag</code>?</p>